Added(A)/Deleted(D) following books

 A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter10_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter11_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter12_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter13_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter14_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter15_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter16_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter2_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter3_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter4_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter5_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter6_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter7_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/Chapter8_1.ipynb
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/screenshots/2correlationCoeff_1.png
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/screenshots/2expansionofSignal_1.png
A  Modern_Digital_And_Analog_Communication_System_by_B._P._Lathi/screenshots/2timeInvertedsignal_1.png
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter10_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter11_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter15_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter1_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter2_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter3_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter5_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter6_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter7_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter8_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/Chapter9_1.ipynb
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/screenshots/ctftch1.png
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/screenshots/fourierTransch1.png
A  Principle_of_Communication_Engineering_by_A._Singh_and_A._K._Chhabra/screenshots/modulatedWaveChap3_1.png
A  Thermodynamics_by_Gaggioli_and_Obert/Ch18.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/Ch8.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch1.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch10.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch11.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch12.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch13.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch14.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch15.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch16.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch17.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch2.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch3.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch5.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch7.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/ch9.ipynb
A  Thermodynamics_by_Gaggioli_and_Obert/screenshots/changeInMoisture14.png
A  Thermodynamics_by_Gaggioli_and_Obert/screenshots/degreeOfSaturation14.png
A  Thermodynamics_by_Gaggioli_and_Obert/screenshots/humidityratio14.png

19 files changed, 5692 insertions, 0 deletions

diff --git a/Thermodynamics_by_Gaggioli_and_Obert/Ch18.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/Ch18.ipynb
new file mode 100644
index 00000000..ef61bd07
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/Ch18.ipynb
@@ -0,0 +1,394 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 18 Refrigeration"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.1 Pg:784"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "Coefficient of performance = 12.0 \n",
+      "\n",
+      " horsepower required per ton of refrigeration = 0.393 hp/ton refrigeration\n",
+      "\n",
+      " Work of compression = -62.8 Btu/lbm\n",
+      "\n",
+      " Work of expansion = 1.42 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "Ta=500 #R\n",
+    "Tr=540 #R\n",
+    "#calculations\n",
+    "cop=Ta/(Tr-Ta)\n",
+    "hp=4.71/cop\n",
+    "print \"From steam tables,\"\n",
+    "ha=48.02\n",
+    "hb=46.6\n",
+    "hc=824.1\n",
+    "hd=886.9\n",
+    "Wc=-(hd-hc)\n",
+    "We=-(hb-ha)\n",
+    "#results\n",
+    "print \"Coefficient of performance = %.1f \"%(cop)\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp)\n",
+    "print \"\\n Work of compression = %.1f Btu/lbm\"%(Wc)\n",
+    "print \"\\n Work of expansion = %.2f Btu/lbm\"%(We)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.2 Pg:785"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Coefficient of performance = 8.96\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "x=0.8\n",
+    "he=26.28 #Btu/lbm\n",
+    "hb=26.28 #Btu/lbm\n",
+    "pe=98.76 #psia\n",
+    "pc=51.68 #psia\n",
+    "hc=82.71 #Btu/lbm\n",
+    "hf=86.80+0.95\n",
+    "#calculations\n",
+    "dwisen=-(hf-hc)\n",
+    "dwact=dwisen/x\n",
+    "hd=hc-dwact\n",
+    "cop=(hc-hb)/(hd-hc)\n",
+    "#results\n",
+    "print \"Coefficient of performance = %.2f\"%(cop)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.3 Pg:785"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Work done = -100.1 Btu/lbm\n",
+      "\n",
+      " horsepower required per ton of refrigeration = 0.994 hp/ton refrigeration\n",
+      "\n",
+      " Coefficient of performance actual = 4.74 \n",
+      "\n",
+      " Ideal cop = 5.737\n",
+      "\n",
+      " relative efficiency = 0.826\n",
+      "\n",
+      " Mass flow rate = 0.422 lbm/min ton\n",
+      "\n",
+      " Compressor capacity = 3.44 cfm/ton\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "hc=613.3#btu/lbm\n",
+    "hb=138.9#btu/lbm\n",
+    "ha=138.9#btu/lbm\n",
+    "hd=713.4 #btu/lbm\n",
+    "ta=464.7 #R\n",
+    "t0=545.7 #R\n",
+    "v=8.150 #ft**3/lbm\n",
+    "#calculations\n",
+    "Qa=hc-hb\n",
+    "Qr=ha-hd\n",
+    "Wcd=Qa+Qr\n",
+    "cop=abs(Qa/Wcd)\n",
+    "hp=abs(4.71/cop)\n",
+    "carnot=abs(ta/(t0-ta))\n",
+    "rel=abs(cop/carnot)\n",
+    "mass=200/Qa\n",
+    "C=mass*v\n",
+    "#results\n",
+    "print \"Work done = %.1f Btu/lbm\"%(Wcd)\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp)\n",
+    "print \"\\n Coefficient of performance actual = %.2f \"%(cop)\n",
+    "print \"\\n Ideal cop = %.3f\"%(carnot)\n",
+    "print \"\\n relative efficiency = %.3f\"%(rel)\n",
+    "print \"\\n Mass flow rate = %.3f lbm/min ton\"%(mass)\n",
+    "print \"\\n Compressor capacity = %.2f cfm/ton\"%(C)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.4 Pg:786"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Pressure ratio = 5.74\n",
+      "\n",
+      " Heat = 25083 Btu/min\n",
+      "\n",
+      " Water make up required = 24.24 lbm/min\n",
+      "\n",
+      " Volume of vapor entering ejector = 58054 cfm\n",
+      "The answers are a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "pc=0.6982 #psia\n",
+    "pe=0.1217 #psia\n",
+    "m=200 #gal/min\n",
+    "qual=0.98\n",
+    "h1=23.07 #Btu/lbm\n",
+    "h2=8.05  #Btu/lbm\n",
+    "hw=1071.3\n",
+    "#calculations\n",
+    "rp=pc/pe\n",
+    "m2=m/0.01602 *0.1388 #Conversion of units \n",
+    "m2=1670\n",
+    "dh=15.02\n",
+    "Qa=m2*(h1-h2)\n",
+    "h3=h2 + qual*hw\n",
+    "m3=Qa/(h3-h1)\n",
+    "v=0.016+ qual*2444\n",
+    "C=m3*v\n",
+    "#results\n",
+    "print \"Pressure ratio = %.2f\"%(rp)\n",
+    "print \"\\n Heat = %d Btu/min\"%(Qa)\n",
+    "print \"\\n Water make up required = %.2f lbm/min\"%(m3)\n",
+    "print \"\\n Volume of vapor entering ejector = %d cfm\"%(C)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.5 Pg:787"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From fig B-4,\n",
+      "Appropraite notation from textbook has been used\n",
+      "All are enthalpy values at different stages\n",
+      "part a\n",
+      "Work done = -18.08 Btu/lbm\n",
+      "\n",
+      " Heat = 47.22 Btu/lbm\n",
+      "\n",
+      " horsepower required per ton of refrigeration = 1.803 hp/ton refrigeration\n",
+      "\n",
+      " Coefficient of performance actual = 2.61 \n",
+      "case 2\n",
+      "\n",
+      " Work done = -53.6 Btu/lbm\n",
+      "\n",
+      " Heat = 146.30 Btu/lbm\n",
+      "\n",
+      " horsepower required per ton of refrigeration = 1.726 hp/ton refrigeration\n",
+      "\n",
+      " Coefficient of performance actual = 2.73 \n",
+      "part b\n",
+      "\n",
+      " Work done = -22.0 Btu/lbm\n",
+      "\n",
+      " Heat = 60.95 Btu/lbm\n",
+      "\n",
+      " horsepower required per ton of refrigeration = 1.702 hp/ton refrigeration\n",
+      "\n",
+      " Coefficient of performance actual = 2.77 \n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "print \"From fig B-4,\"\n",
+    "print \"Appropraite notation from textbook has been used\"\n",
+    "print \"All are enthalpy values at different stages\"\n",
+    "hc=73.5 #Btu/lbm\n",
+    "hb=26.28 #Btu/lbm\n",
+    "hd=91.58 #Btu/lbm\n",
+    "hc2=190.7 #Btu/lbm\n",
+    "hd2=244.3 #Btu/lbm\n",
+    "hb2=44.4 #Btu/lbm\n",
+    "m1=1 #lbm\n",
+    "m2=0.461 #lbm\n",
+    "hc1=73.5 #Btu/lbm\n",
+    "hd1=83.35 #Btu/lbm \n",
+    "hc2=190.7 #Btu/lbm \n",
+    "hd2=244.3 #Btu/lbm\n",
+    "hb1=12.55 #Btu/lbm \n",
+    "hc22=197.58 #Btu/lbm \n",
+    "hd22=224 #Btu/lbm\n",
+    "#Calculations\n",
+    "w1=hc-hd\n",
+    "qa1=hc-hb\n",
+    "cop1=abs(qa1/(w1))\n",
+    "hp1=4.71/cop1\n",
+    "w2=hc2-hd2\n",
+    "qa2=hc2-hb2\n",
+    "cop2=abs(qa2/(w2))\n",
+    "hp2=4.71/cop2\n",
+    "qa3=m1*(hc1-hb1)\n",
+    "w3=m1*(hc1-hd1) + m2*(hc22-hd22)\n",
+    "cop3=abs(qa3/w3)\n",
+    "hp3=4.71/cop3\n",
+    "#results\n",
+    "print \"part a\"\n",
+    "print \"Work done = %.2f Btu/lbm\"%(w1)\n",
+    "print \"\\n Heat = %.2f Btu/lbm\"%(qa1)\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp1)\n",
+    "print \"\\n Coefficient of performance actual = %.2f \"%(cop1)\n",
+    "print \"case 2\"\n",
+    "print \"\\n Work done = %.1f Btu/lbm\"%(w2)\n",
+    "print \"\\n Heat = %.2f Btu/lbm\"%(qa2)\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp2)\n",
+    "print \"\\n Coefficient of performance actual = %.2f \"%(cop2)\n",
+    "print \"part b\"\n",
+    "print \"\\n Work done = %.1f Btu/lbm\"%(w3)\n",
+    "print \"\\n Heat = %.2f Btu/lbm\"%(qa3)\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp3)\n",
+    "print \"\\n Coefficient of performance actual = %.2f \"%(cop3)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:18.6 Pg:788"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From fig B-4,\n",
+      "Appropraite notation from textbook has been used\n",
+      "All are enthalpy values at different stages\n",
+      "\n",
+      " horsepower required per ton of refrigeration = 1.585 hp/ton refrigeration\n",
+      "\n",
+      " Coefficient of performance actual = 2.97 \n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "print \"From fig B-4,\"\n",
+    "print \"Appropraite notation from textbook has been used\"\n",
+    "print \"All are enthalpy values at different stages\"\n",
+    "ha=44.36 #Btu/lbm \n",
+    "hc=18.04 #Btu/lbm\n",
+    "hj=197.58 #Btu/lbm\n",
+    "hh=213.5 #Btu/lbm \n",
+    "hd=hc #Btu/lbm\n",
+    "he=190.66 #Btu/lbm\n",
+    "hk=241.25 #Btu/lbm\n",
+    "#calculations\n",
+    "m=(hc-ha)/(ha-hj)\n",
+    "hi=(m*hj+hh)/(1+m)\n",
+    "Qa=he-hd\n",
+    "W=he-hh + (1+m)*(hi-hk)\n",
+    "cop=abs(Qa/W)\n",
+    "hp=4.71/cop\n",
+    "#results\n",
+    "print \"\\n horsepower required per ton of refrigeration = %.3f hp/ton refrigeration\"%(hp)\n",
+    "print \"\\n Coefficient of performance actual = %.2f \"%(cop)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/Ch8.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/Ch8.ipynb
new file mode 100644
index 00000000..2e3ca609
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/Ch8.ipynb
@@ -0,0 +1,149 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 8 Second and third law topics"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:8.1 Pg:255"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "dp by ds at constant volume = 275 F/ft**3/lbm\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P=500 #psia\n",
+    "T=700 #F\n",
+    "J=778\n",
+    "#calculations\n",
+    "dpds=1490 *144/J\n",
+    "#results\n",
+    "print \"dp by ds at constant volume = %d F/ft**3/lbm\"%(dpds)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:8.2 Pg:256"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Thermal efficiency = 66.5 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "cp=0.25 #Btu/lbm R\n",
+    "T0=520 #R\n",
+    "T1=3460 #R\n",
+    "#calculations\n",
+    "dq=cp*(T0-T1)\n",
+    "ds=cp*log(T0/T1)\n",
+    "dE=dq-T0*ds\n",
+    "eta=dE/dq\n",
+    "#results\n",
+    "print \"Thermal efficiency = %.1f percent\"%(eta*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:8.3 Pg:256"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Loss of available energy = -6774 Btu/lbm\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "cp=0.25 #Btu/lbm R\n",
+    "T0=520 #R\n",
+    "T1=3460 #R\n",
+    "dG=21069 #Btu/lbm\n",
+    "dH=21502 #Btu/lbm\n",
+    "#calculations\n",
+    "dq=cp*(T0-T1)\n",
+    "ds=cp*log(T0/T1)\n",
+    "dE=dq-T0*ds\n",
+    "eta=dE/dq\n",
+    "dw=eta*dH\n",
+    "de=-dG+dw\n",
+    "#results\n",
+    "print \"Loss of available energy = %d Btu/lbm\"%(de)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch1.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch1.ipynb
new file mode 100644
index 00000000..56ea81cb
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch1.ipynb
@@ -0,0 +1,227 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 1 Survey Of Units And Dimensions"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.1 Pg: 19"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Force to accelerate = 3.108 lbf\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "gc=32.1739 #lbm ft/lbf s**2\n",
+    "m=10 #lbm\n",
+    "a=10 #ft/s**2\n",
+    "#calculations\n",
+    "F=m*a/gc\n",
+    "#results\n",
+    "print \"Force to accelerate = %.3f lbf\"%(F)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.2 Pg: 19"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Force to accelerate = 10 lbf\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "gc=32.1739 #lbm ft/lbf s**2\n",
+    "m=10 #lbm\n",
+    "a=gc #ft/s**2\n",
+    "#calculations\n",
+    "F=m*a/gc\n",
+    "#results\n",
+    "print \"Force to accelerate = %d lbf\"%(F)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.3 Pg: 19"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "velocity = 60 mph\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "v=88 #ft/s\n",
+    "#calculations\n",
+    "v2=v*3600/5280\n",
+    "#results\n",
+    "print \"velocity = %d mph\"%(v2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.4 Pg: 20"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "velocity = 0 mph\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "v=88 #ft/s\n",
+    "#calculations\n",
+    "v2=v*1/5280*3600\n",
+    "#results\n",
+    "print \"velocity = %d mph\"%(v2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.5 Pg: 20"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Force without dimensions = 5.79e-04 lbm/ft sec\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "F=5e-9 #lbf/ft**2 hr\n",
+    "g=32.1739\n",
+    "#calculations\n",
+    "F2=F*3600*g\n",
+    "#results\n",
+    "print \"Force without dimensions = %.2e lbm/ft sec\"%(F2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:1.6 Pg: 21"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Density of water in this system = 1.937 lbf/ft**2\n",
+      "\n",
+      " Specific weight = 62.305 lbf/ft**2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "rho=62.305 #lbf/ft**2\n",
+    "g=32.1739 #ft/s**2\n",
+    "#calculations\n",
+    "gam=rho/g\n",
+    "#results\n",
+    "print \"Density of water in this system = %.3f lbf/ft**2\"%(gam)\n",
+    "print \"\\n Specific weight = %.3f lbf/ft**2\"%(rho)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch10.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch10.ipynb
new file mode 100644
index 00000000..4ac6845c
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch10.ipynb
@@ -0,0 +1,157 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 10 The pvt relationships"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:10.1 Pg:360"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "For ideal gas case, Table B-6 and for vanderwaals case, Table B-8 have been used\n",
+      "\n",
+      " In vanderwaals equation, pressure = 50.0 atm\n",
+      "\n",
+      " In ideal gas case, pressure = 57.8 atm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m=1 #lbm\n",
+    "T1=212+460 #R\n",
+    "sv=0.193 #ft**3/lbm\n",
+    "M=44\n",
+    "a=924.2 #atm ft**2 /mole**2\n",
+    "b=0.685 #ft**3/mol\n",
+    "R=0.73 #atm ft**3/R mol\n",
+    "#calculations\n",
+    "v=sv*M\n",
+    "p=R*T1/v\n",
+    "p2=R*T1/(v-b) -a/v**2\n",
+    "#results\n",
+    "print \"For ideal gas case, Table B-6 and for vanderwaals case, Table B-8 have been used\"\n",
+    "print \"\\n In vanderwaals equation, pressure = %.1f atm\"%(p2)\n",
+    "print \"\\n In ideal gas case, pressure = %.1f atm\"%(p)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:10.2 Pg:360"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "volume = 8.481 ft**3/mole\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m=1 #lbm\n",
+    "p=50.9 #atm\n",
+    "t=212+460 #R\n",
+    "R=0.73\n",
+    "#calculations\n",
+    "pc=72.9 #atm\n",
+    "tc=87.9 +460 #R\n",
+    "pr=p/pc\n",
+    "Tr=t/tc\n",
+    "z=0.88\n",
+    "v=z*R*t/p\n",
+    "#results\n",
+    "print \"volume = %.3f ft**3/mole\"%(v)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:10.3 Pg:361"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Pressure = 50.8 atm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t=212+460 #R\n",
+    "v=0.193 #ft**3/lbm\n",
+    "M=44\n",
+    "R=0.73\n",
+    "#calculations\n",
+    "tc=87.9+460 #F\n",
+    "zc=0.275\n",
+    "vc=1.51 #ft**3/mol\n",
+    "tr=t/tc\n",
+    "vr=v*M/vc\n",
+    "vrd=vr*zc\n",
+    "z=0.88\n",
+    "p=z*R*t/(M*v)\n",
+    "#results\n",
+    "print \"Pressure = %.1f atm\"%(p)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch11.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch11.ipynb
new file mode 100644
index 00000000..001bcdc2
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch11.ipynb
@@ -0,0 +1,762 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 11 The ideal gas and mixture relationship"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.1 Pg:415"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Work done = -58682 ft-lbf/lbm\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "n=1.3\n",
+    "T1=460+60 #R\n",
+    "P1=14.7 #psia\n",
+    "P2=125 #psia\n",
+    "R=1545\n",
+    "M=29\n",
+    "#calculations\n",
+    "T2=T1*(P2/P1)**((n-1)/n)\n",
+    "wrev=R/M *(T2-T1)/(1-n)\n",
+    "#results\n",
+    "print \"Work done = %d ft-lbf/lbm\"%(wrev)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.2 Pg:415"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in kinetic energy = 52.3 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P2=10 #psia\n",
+    "P1=100 #psia\n",
+    "T1=900 #R\n",
+    "w=50 #Btu/lbm\n",
+    "k=1.39\n",
+    "cp=0.2418\n",
+    "#calculations\n",
+    "T2=T1*(P2/P1)**((k-1)/k)\n",
+    "T2=477\n",
+    "KE=-w-cp*(T2-T1)\n",
+    "#results\n",
+    "print \"Change in kinetic energy = %.1f Btu/lbm\"%(KE)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.3 Pg:416"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-9\n",
+      "Final temperature = 468 R \n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "T1=900 #R\n",
+    "P1=100 #psia\n",
+    "P2=10 #psia\n",
+    "#calculations\n",
+    "print \"From table B-9\"\n",
+    "pr1=8.411\n",
+    "pr2=pr1*P2/P1\n",
+    "T2=468 #R\n",
+    "#results\n",
+    "print \"Final temperature = %d R \"%(T2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.4 Pg:417"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from table b-9\n",
+      "final temperature = 1050 R\n",
+      "\n",
+      " final pressure = 177.7 psia\n",
+      "\n",
+      " work done = -92.85 Btu/lbm\n",
+      "\n",
+      " final enthalpy = 253.4 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "cr=6\n",
+    "p1=14.7 #psia\n",
+    "t1=60.3 #F\n",
+    "M=29\n",
+    "R=1.986\n",
+    "#calculations\n",
+    "print \"from table b-9\"\n",
+    "vr1=158.58 \n",
+    "u1=88.62 #Btu/lbm\n",
+    "pr1=1.2147\n",
+    "vr2=vr1/cr\n",
+    "T2=1050 #R\n",
+    "u2=181.47 #Btu/lbm\n",
+    "pr2=14.686\n",
+    "p2=p1*(pr2/pr1)\n",
+    "dw=u1-u2\n",
+    "h2=u2+T2*R/M\n",
+    "#results\n",
+    "print \"final temperature = %d R\"%(T2)\n",
+    "print \"\\n final pressure = %.1f psia\"%(p2)\n",
+    "print \"\\n work done = %.2f Btu/lbm\"%(dw)\n",
+    "print \"\\n final enthalpy = %.1f Btu/lbm\"%(h2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.5 Pg:417"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "part a\n",
+      "Mole fractions of oxygen and nitrogen are 0.369 and 0.631 respectively\n",
+      "part b\n",
+      "Average molecular weight = 29.5 \n",
+      "part c\n",
+      "specific gas constant = 0.3639 psia ft**3/lbm R\n",
+      "part d\n",
+      "volume of mixture = 94.6 ft**3\n",
+      "density of mixture is 0.00896 mole/ft**3 and 0.26 lbm/ft**3\n",
+      "part e\n",
+      "partial pressures of oxygen and nitrogen are 18.43 psia and 31.57 psia respectively\n",
+      "part a\n",
+      "Mole fractions of oxygen and nitrogen are 0.369 and 0.631 respectively\n",
+      "part b\n",
+      "Average molecular weight = 29.5 \n",
+      "part c\n",
+      "specific gas constant = 52.3960 lbf ft/lbm R\n",
+      "part d\n",
+      "volume of mixture = 94.6 ft**3\n",
+      "\n",
+      " density of mixture is 0.00896 mole/ft**3 and 0.264 lbm/ft**3\n",
+      "part e\n",
+      "partial pressures of oxygen and nitrogen are 18.43 psia and 31.57 psia respectively\n",
+      "\n",
+      " partial volumes of oxygen and nitrogen are 34.87 ft**3 and 59.74 ft**3 respectively\n",
+      "\n",
+      " Net partial pressure in case of oxygen = 50.00 psia\n",
+      "\n",
+      " Net partial volume =94.61 ft**3\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "#Initialization of variables\n",
+    "m1=10 #lbm\n",
+    "m2=15 #lnm\n",
+    "p=50 #psia\n",
+    "t=60+460 #R\n",
+    "M1=32\n",
+    "M2=28.02\n",
+    "R0=10.73 \n",
+    "#calculations\n",
+    "n1=m1/M1\n",
+    "n2=m2/M2\n",
+    "x1=n1/(n1+n2)\n",
+    "x2=n2/(n1+n2)\n",
+    "M=x1*M1+x2*M2\n",
+    "R=R0/M\n",
+    "V=(n1+n2)*R0*t/p\n",
+    "rho=p/(R0*t)\n",
+    "rho2=M*rho\n",
+    "p1=x1*p\n",
+    "p2=x2*p\n",
+    "v1=x1*V\n",
+    "v2=x2*V\n",
+    "#results\n",
+    "print \"part a\"\n",
+    "print \"Mole fractions of oxygen and nitrogen are %.3f and %.3f respectively\"%(x1,x2)\n",
+    "print \"part b\"\n",
+    "print \"Average molecular weight = %.1f \"%(M)\n",
+    "print \"part c\"\n",
+    "print \"specific gas constant = %.4f psia ft**3/lbm R\"%(R)\n",
+    "print \"part d\"\n",
+    "print \"volume of mixture = %.1f ft**3\"%(V)\n",
+    "print \"density of mixture is %.5f mole/ft**3 and %.2f lbm/ft**3\"%(rho,rho2)\n",
+    "print \"part e\"\n",
+    "print \"partial pressures of oxygen and nitrogen are %.2f psia and %.2f psia respectively\"%(p1,p2)\n",
+    "#Initialization of variables\n",
+    "m1=10 #lbm\n",
+    "m2=15 #lnm\n",
+    "p=50 #psia\n",
+    "t=60+460 #R\n",
+    "M1=32\n",
+    "M2=28.02\n",
+    "R0=10.73 \n",
+    "#calculations\n",
+    "n1=m1/M1\n",
+    "n2=m2/M2\n",
+    "x1=n1/(n1+n2)\n",
+    "x2=n2/(n1+n2)\n",
+    "M=x1*M1+x2*M2\n",
+    "R=1545/M\n",
+    "V=(n1+n2)*R0*t/p\n",
+    "rho=p/(R0*t)\n",
+    "rho2=M*rho\n",
+    "p1=x1*p\n",
+    "p2=x2*p\n",
+    "v1=x1*V\n",
+    "v2=x2*V\n",
+    "pt=p1+p2\n",
+    "vt=v1+v2\n",
+    "#results\n",
+    "print \"part a\"\n",
+    "print \"Mole fractions of oxygen and nitrogen are %.3f and %.3f respectively\"%(x1,x2)\n",
+    "print \"part b\"\n",
+    "print \"Average molecular weight = %.1f \"%(M)\n",
+    "print \"part c\"\n",
+    "print \"specific gas constant = %.4f lbf ft/lbm R\"%(R)\n",
+    "print \"part d\"\n",
+    "print \"volume of mixture = %.1f ft**3\"%(V)\n",
+    "print \"\\n density of mixture is %.5f mole/ft**3 and %.3f lbm/ft**3\"%(rho,rho2)\n",
+    "print \"part e\"\n",
+    "print \"partial pressures of oxygen and nitrogen are %.2f psia and %.2f psia respectively\"%(p1,p2)\n",
+    "print \"\\n partial volumes of oxygen and nitrogen are %.2f ft**3 and %.2f ft**3 respectively\"%(v1,v2)\n",
+    "print \"\\n Net partial pressure in case of oxygen = %.2f psia\"%(pt)\n",
+    "print \"\\n Net partial volume =%.2f ft**3\"%(vt)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.6 Pg:418"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From gravimetric analysis, co2 = 17.6 percent , o2 = 4.3 percent and n2 = 78.2 percent\n",
+      "\n",
+      " From ultimate analysis, co2 = 0.00 percent , o2 = 4.26 percent and n2 = 78.19 percent\n",
+      "\n",
+      " Sum in case 1 = 100.0 percent\n",
+      "\n",
+      " Sum in case 2 = 82.4 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m1=5.28\n",
+    "m2=1.28\n",
+    "m3=23.52\n",
+    "#calculations\n",
+    "m=m1+m2+m3\n",
+    "x1=m1/m\n",
+    "x2=m2/m\n",
+    "x3=m3/m\n",
+    "C=12/44 *m1/ m\n",
+    "O=(32/44 *m1 + m2)/m\n",
+    "N=m3/m\n",
+    "sum1=(x1+x2+x3)*100\n",
+    "sum2=(C+N+O)*100\n",
+    "#results\n",
+    "print \"From gravimetric analysis, co2 = %.1f percent , o2 = %.1f percent and n2 = %.1f percent\"%(x1*100,x2*100,x3*100)\n",
+    "print \"\\n From ultimate analysis, co2 = %.2f percent , o2 = %.2f percent and n2 = %.2f percent\"%(C*100,O*100,N*100)\n",
+    "print \"\\n Sum in case 1 = %.1f percent\"%(sum1)\n",
+    "print \"\\n Sum in case 2 = %.1f percent\"%(sum2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.7 Pg:419"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Entropy of mixture = 8.27 Btu/R\n",
+      "\n",
+      " the answer given in textbook is wrong. please check using a calculator\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from scipy import log\n",
+    "#Initialization of variables\n",
+    "x1=1/3\n",
+    "n1=1\n",
+    "n2=2\n",
+    "x2=2/3\n",
+    "p=12.7 #psia\n",
+    "cp1=7.01 #Btu/mole R\n",
+    "cp2=6.94 #Btu/mole R\n",
+    "R0=1.986\n",
+    "T2=460+86.6 #R\n",
+    "T1=460 #R\n",
+    "p0=14.7 #psia\n",
+    "#calculations\n",
+    "p1=x1*p\n",
+    "p2=x2*p\n",
+    "ds1= cp1*log(T2/T1) - R0*log(p1/p0)\n",
+    "ds2= cp2*log(T2/T1) - R0*log(p2/p0)\n",
+    "S=n1*ds1+n2*ds2\n",
+    "#results\n",
+    "print \"Entropy of mixture = %.2f Btu/R\"%(S)\n",
+    "print \"\\n the answer given in textbook is wrong. please check using a calculator\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.8 Pg:420"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in internal energy = -547 Btu\n",
+      "\n",
+      " Change in entropy = -1.037 Btu/R\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from scipy import log\n",
+    "\n",
+    "#Initialization of variables\n",
+    "c1=4.97 #Btu/mol R\n",
+    "c2=5.02 #Btu/mol R\n",
+    "n1=2\n",
+    "n2=1\n",
+    "T1=86.6+460 #R\n",
+    "T2=50+460 #R\n",
+    "#calculations\n",
+    "du=(n1*c1+n2*c2)*(T2-T1)\n",
+    "ds=(n1*c1+n2*c2)*log(T2/T1)\n",
+    "#results\n",
+    "print \"Change in internal energy = %d Btu\"%(du)\n",
+    "print \"\\n Change in entropy = %.3f Btu/R\"%(ds)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.9 Pg:420"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Pressure of mixture = 12.7 psia\n",
+      "\n",
+      " Mixing temperature = 86.6 F\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "\n",
+    "#Initialization of variables\n",
+    "n1=1\n",
+    "n2=2\n",
+    "c1=5.02\n",
+    "c2=4.97\n",
+    "t1=60 #F\n",
+    "t2=100 #F\n",
+    "R0=10.73\n",
+    "p1=30 #psia\n",
+    "p2=10 #psia\n",
+    "#calcualtions\n",
+    "t=(n1*c1*t1+n2*c2*t2)/(n1*c1+n2*c2)\n",
+    "V1= n1*R0*(t1+460)/p1\n",
+    "V2=n2*R0*(t2+460)/p2\n",
+    "V=V1+V2\n",
+    "pm=(n1+n2)*R0*(t+460)/V\n",
+    "#results\n",
+    "print \"Pressure of mixture = %.1f psia\"%(pm)\n",
+    "print \"\\n Mixing temperature = %.1f F\"%(t)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.10 Pg:421"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in  entropy for gas 1 = 4.242 Btu/R\n",
+      "\n",
+      " Change in  entropy for gas 1 = 0.331 Btu/R\n",
+      "\n",
+      " Net change in entropy = 4.572 Btu/R\n",
+      "\n",
+      " In case 2, change in entropy = 4.572 Btu/R\n",
+      "The answer is a bit different due to rounding off error in the textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from scipy import log\n",
+    "\n",
+    "#Initialization of variables\n",
+    "T2=546.6 #R\n",
+    "T1=520 #R\n",
+    "T3=560 #R\n",
+    "v2=1389.2\n",
+    "v1=186.2\n",
+    "R0=1.986\n",
+    "c1=5.02\n",
+    "c2=4.97\n",
+    "n1=1\n",
+    "n2=2\n",
+    "v3=1203\n",
+    "#calculations\n",
+    "ds1=n1*c1*log(T2/T1) + n1*R0*log(v2/v1)\n",
+    "ds2=n2*c2*log(T2/T3)+n2*R0*log(v2/v3)\n",
+    "ds=ds1+ds2\n",
+    "ds3=n1*c1*log(T2/T1)+n2*c2*log(T2/T3)\n",
+    "ds4=n2*R0*log(v2/v3)+ n1*R0*log(v2/v1)\n",
+    "dss=ds3+ds4\n",
+    "#results\n",
+    "print \"Change in  entropy for gas 1 = %.3f Btu/R\"%(ds1)\n",
+    "print \"\\n Change in  entropy for gas 1 = %.3f Btu/R\"%(ds2)\n",
+    "print \"\\n Net change in entropy = %.3f Btu/R\"%(ds)\n",
+    "print \"\\n In case 2, change in entropy = %.3f Btu/R\"%(dss)\n",
+    "print \"The answer is a bit different due to rounding off error in the textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.11 Pg:42"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Final remperature = 851 R\n",
+      "\n",
+      " Change in entropy of air = -0.115 btu/mole R and -0.00395 Btu/R\n",
+      "\n",
+      " Change in entropy of water = 0.0757 btu/mole R and 0.00395 Btu/R\n",
+      "The answers are a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from scipy import log\n",
+    "\n",
+    "#Initialization of variables\n",
+    "m1=1 #lbm\n",
+    "m2=0.94 #lbm\n",
+    "M1=29\n",
+    "M2=18\n",
+    "p1=50 #psia\n",
+    "p2=100 #psia\n",
+    "t1=250 +460 #R\n",
+    "R0=1.986\n",
+    "cpa=6.96\n",
+    "cpb=8.01\n",
+    "#calculations\n",
+    "xa = (m1/M1)/((m1/M1)+ m2/M2)\n",
+    "xb=1-xa\n",
+    "t2=t1*(p2/p1)**(R0/(xa*cpa+xb*cpb))\n",
+    "d=R0/(xa*cpa+xb*cpb)\n",
+    "k=1/(1-d)\n",
+    "dsa=cpa*log(t2/t1) -R0*log(p2/p1)\n",
+    "dSa=(m1/M1)*dsa\n",
+    "dSw=-dSa\n",
+    "dsw=dSw*M2/m2\n",
+    "#results\n",
+    "print \"Final remperature = %d R\"%(t2)\n",
+    "print \"\\n Change in entropy of air = %.3f btu/mole R and %.5f Btu/R\"%(dsa,dSa)\n",
+    "print \"\\n Change in entropy of water = %.4f btu/mole R and %.5f Btu/R\"%(dsw,dSw)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.12 Pg:423"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "In case 1, volume occupied = 13.02 ft**3\n",
+      "\n",
+      " In case 1, mass of steam = 0.94 lbm steam\n",
+      "\n",
+      " In case 2, mass of steam = 0.918 lbm steam\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "\n",
+    "#Initialization of variables\n",
+    "T=250 + 460 #R\n",
+    "p=29.825 #psia\n",
+    "pt=50 #psia\n",
+    "vg=13.821 #ft**3/lbm\n",
+    "M=29\n",
+    "R=10.73\n",
+    "#calculations\n",
+    "pa=pt-p\n",
+    "V=1/M *R*T/pa\n",
+    "ma=V/vg\n",
+    "xa=p/pt\n",
+    "mb=xa/M *18/(1-xa)\n",
+    "#results\n",
+    "print \"In case 1, volume occupied = %.2f ft**3\"%(V)\n",
+    "print \"\\n In case 1, mass of steam = %.2f lbm steam\"%(ma)\n",
+    "print \"\\n In case 2, mass of steam = %.3f lbm steam\"%(mb)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.13 Pg:424"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "percentage = 65.0 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "\n",
+    "#Initialization of variables\n",
+    "ps=0.64 #psia\n",
+    "p=14.7 #psia\n",
+    "M=29\n",
+    "M2=46\n",
+    "#calculations\n",
+    "xa=ps/p\n",
+    "mb=xa*9/M *M2/(1-xa)\n",
+    "#results\n",
+    "print \"percentage = %.1f percent\"%(mb*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:11.14 Pg:424"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "partial pressure of water vapor = 0.317 psia\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "\n",
+    "#Initialization of variables\n",
+    "ps=0.5069 #psia\n",
+    "p=20 #psia\n",
+    "m1=0.01\n",
+    "m2=1\n",
+    "M1=18\n",
+    "M2=29\n",
+    "#calculations\n",
+    "xw= (m1/M1)/(m1/M1+m2/M2)\n",
+    "pw=xw*p\n",
+    "#results\n",
+    "print \"partial pressure of water vapor = %.3f psia\"%(pw)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch12.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch12.ipynb
new file mode 100644
index 00000000..c7c68649
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch12.ipynb
@@ -0,0 +1,402 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 12 Non steady flow friction and availibility"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.1 Pg:482"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Work done in case 1 = 572 Btu\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p1=100 #psia\n",
+    "p2=14.7 #psia\n",
+    "k=1.4\n",
+    "T1=700 #R\n",
+    "R=10.73/29\n",
+    "V=50\n",
+    "cv=0.171\n",
+    "cp=0.24\n",
+    "R2=1.986/29\n",
+    "#calculations\n",
+    "T2=T1/ (p1/p2)**((k-1)/k)\n",
+    "m1=p1*V/(R*T1)\n",
+    "m2=p2*V/(R*T2)\n",
+    "Wrev= cv*(m1*T1 - m2*T2) - (m1-m2)*(T2)*cp\n",
+    "#results\n",
+    "print \"Work done in case 1 = %d Btu\"%(Wrev)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.2 Pg:482"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The friction of the process per pound of air = 18.6 Btu/lbm\n",
+      "\n",
+      " Loss of available energy = -16.20 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from scipy import log\n",
+    "#Initialization of variables\n",
+    "p1=100 #psia\n",
+    "p2=10 #psia\n",
+    "n=1.3\n",
+    "T1=800 #R\n",
+    "cv=0.172\n",
+    "R=1.986/29\n",
+    "T0=537 #R\n",
+    "cp=0.24\n",
+    "#calculations\n",
+    "T2=T1*(p2/p1)**((n-1)/n)\n",
+    "dwir=cv*(T1-T2)\n",
+    "dwr=R*(T2-T1)/(1-n)\n",
+    "dq=dwr-dwir\n",
+    "dI=-T0*(cp*log(T2/T1) - R*log(p2/p1))\n",
+    "#results\n",
+    "print \"The friction of the process per pound of air = %.1f Btu/lbm\"%(dq)\n",
+    "print \"\\n Loss of available energy = %.2f Btu/lbm\"%(dI)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.3 Pg:483"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Friction = 72.9 ft-lbf/lbm\n",
+      "\n",
+      " Available energy loss in case a = -72.9 ft-lbf/lbm\n",
+      "\n",
+      " Available energy loss in case b = -145.9 ft-lbf/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "ms=10 #lbm\n",
+    "den=62.3 #lbm/ft**3\n",
+    "A1=0.0218 #ft**2\n",
+    "A2=0.00545 #ft**2\n",
+    "p2=50 #psia\n",
+    "p1=100 #psia\n",
+    "gc=32.2 #ft/s**2\n",
+    "dz=30 #ft\n",
+    "T0=537 #R\n",
+    "T1=620 #R\n",
+    "T2=420 #R\n",
+    "#calculations\n",
+    "V1=ms/(A1*den)\n",
+    "V2=ms/(A2*den)\n",
+    "df=-144/den*(p2-p1) - (V2**2 -V1**2)/(2*gc) - dz\n",
+    "dI=-T0/T1 *df\n",
+    "dI2= -T0/T2 *df\n",
+    "#results\n",
+    "print \"Friction = %.1f ft-lbf/lbm\"%(df)\n",
+    "print \"\\n Available energy loss in case a = %.1f ft-lbf/lbm\"%(dI)\n",
+    "print \"\\n Available energy loss in case b = %.1f ft-lbf/lbm\"%(dI2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.4 Pg:484"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From fig 12.4,\n",
+      "Pressure drop = 0.00 lbf/ft**2 100 ft\n",
+      "The answer in the textbook is wrong. Please use a calculator to verify it.\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "r=2.5 #in\n",
+    "mf=160 #cfm\n",
+    "rho=1/14\n",
+    "mu=0.0000121\n",
+    "v=14 #ft**3/lbm\n",
+    "g=32.2 #ft/s**2\n",
+    "z=100 #ft\n",
+    "#calculations\n",
+    "A=3.14*(r/12)**2\n",
+    "V=mf/A /60\n",
+    "Re=(2*r/12)*V*rho/mu\n",
+    "print \"From fig 12.4,\"\n",
+    "f=0.0225/4\n",
+    "dp=4*f*(rho)*(V/v)**2 /(2*g*(2*r/12)) *z\n",
+    "#dp=2.32\n",
+    "#results\n",
+    "print \"Pressure drop = %.2f lbf/ft**2 100 ft\"%(dp)\n",
+    "print \"The answer in the textbook is wrong. Please use a calculator to verify it.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.5 Pg:485"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Mass rate of air flow = 161 cfm\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "D=0.0724 #ft\n",
+    "gc=32.2 #ft/s**2\n",
+    "rho=1.0/14\n",
+    "L=100 #ft\n",
+    "mu2=1.46*10**(-10)\n",
+    "dp=2.32\n",
+    "dia=5.0 #in\n",
+    "rho2=48500.0\n",
+    "vol=14.0 #ft**3/lbm\n",
+    "#calculations\n",
+    "ref=D**3 *2*dp*gc*rho/(mu2*L)\n",
+    "mf=rho2*pi/4 *(dia/12) *sqrt(mu2)\n",
+    "mfr=mf*vol*60\n",
+    "#results\n",
+    "print \"Mass rate of air flow = %d cfm\"%(mfr)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.6 Pg:486"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Loss of available energy = -725 Btu/lbm mixture \n",
+      "\n",
+      " Effectiveness of combustion = 0.409 \n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "cp=0.25\n",
+    "T=3460 #R\n",
+    "T0=520 #R\n",
+    "dG=1228 #Btu/lbm\n",
+    "#calculations\n",
+    "hf=cp*(T-T0)-T0*cp*log(T/T0)\n",
+    "dC=hf-dG\n",
+    "Ec=hf/dG\n",
+    "#results\n",
+    "print \"Loss of available energy = %d Btu/lbm mixture \"%(dC)\n",
+    "print \"\\n Effectiveness of combustion = %.3f \"%(Ec)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.7 Pg:487"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Loss of available energy = -219.3 Btu/lbm mixture \n",
+      "\n",
+      " Efficiency of cycle = 0.563 \n",
+      "\n",
+      " Effectiveness of overall cycle = 0.23\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "cp1=0.25\n",
+    "T=3460 #R\n",
+    "T0=946.2 #R\n",
+    "T00=520 #R\n",
+    "dG=1228 #Btu/lbm\n",
+    "cp=0.45\n",
+    "#calculations\n",
+    "dqa=cp1*(T-T0)\n",
+    "w=cp*dqa\n",
+    "hf=cp1*(T-T00)-T00*cp1*log(T/T00)\n",
+    "heat=w-hf\n",
+    "eff=w/hf\n",
+    "epower=w/dG\n",
+    "#results\n",
+    "print \"Loss of available energy = %.1f Btu/lbm mixture \"%(heat)\n",
+    "print \"\\n Efficiency of cycle = %.3f \"%(eff)\n",
+    "print \"\\n Effectiveness of overall cycle = %.2f\"%(epower)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:12.8 Pg:487"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "All the values are obtained from Mollier chart,\n",
+      "Engine efficiency = 74.3 percent\n",
+      "\n",
+      " Effectiveness = 80.8 percent\n",
+      "\n",
+      " Loss of available energy  = -32.6 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p1=400 #psia\n",
+    "t1=600 #F\n",
+    "h1=1306.9 #Btu/lbm\n",
+    "b1=480.9 #Btu/lbm\n",
+    "p2=50 #psia\n",
+    "h2=1122 #Btu/lbm\n",
+    "h3=1169.5 #Btu/lbm\n",
+    "b3=310.9 #Btu/lbm\n",
+    "#calculations\n",
+    "print \"All the values are obtained from Mollier chart,\"\n",
+    "dw13=h1-h3\n",
+    "dw12=h1-h2\n",
+    "dasf=b3-b1\n",
+    "etae=dw13/dw12\n",
+    "eta=abs(dw13/dasf)\n",
+    "dq=dw13+dasf\n",
+    "#results\n",
+    "print \"Engine efficiency = %.1f percent\"%(etae*100)\n",
+    "print \"\\n Effectiveness = %.1f percent\"%(eta*100)\n",
+    "print \"\\n Loss of available energy  = %.1f Btu/lbm\"%(dq)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch13.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch13.ipynb
new file mode 100644
index 00000000..efe4a78b
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch13.ipynb
@@ -0,0 +1,798 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 13 Fluid flow"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.1 Pg:583"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "velocity in ft/s are:\n",
+      "0.000000 \t1118.735268 \t1663.871913 \t1791.374302 \t2179.668416 \t2779.331106 \t\n",
+      "\n",
+      "Area in ft**2 are:\n",
+      "0.000000 \t0.006600 \t0.005534 \t0.005495 \t0.005760 \t0.007656 \t\n",
+      "\n",
+      "The initial values of velocity and area are 0 and infinity respectively. Since, Infinity in calculations stops the code to display an error. It has been mentioned separately.\n"
+     ]
+    }
+   ],
+   "source": [
+    "from numpy import nditer\n",
+    "from math import sqrt\n",
+    "#Initialization of variables\n",
+    "h1=1329.1 #Btu/lbm\n",
+    "v1=6.218 #ft**3/lbm\n",
+    "J=778\n",
+    "g=32.174\n",
+    "m=1\n",
+    "#calculations\n",
+    "p=[80, 60 ,54.6, 40, 20]\n",
+    "h=[ 1304.1, 1273.8, 1265 ,1234.2, 1174.8]\n",
+    "v=[ 7.384, 9.208, 9.844 ,12.554, 21.279]\n",
+    "Fc=1\n",
+    "V2=[Fc*sqrt(2*J*g*(h1-hh)) for hh in h]\n",
+    "A=[m*v1/V21 for v1,V21 in nditer([v,V2])]\n",
+    "V2=[0]+V2\n",
+    "A=[0]+A\n",
+    "#results\n",
+    "print 'velocity in ft/s are:'\n",
+    "for vv in V2:\n",
+    "    print '%.6f'%vv,'\\t', \n",
+    "print '\\n\\nArea in ft**2 are:'\n",
+    "for aa in A:\n",
+    "    print '%.6f'%aa,'\\t',\n",
+    "print '\\n\\nThe initial values of velocity and area are 0 and infinity respectively. Since, Infinity in calculations stops the code to display an error. It has been mentioned separately.'"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.2 Pg:584"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Area required = 0.00464 ft**2\n",
+      "\n",
+      " Area in case 2 at the exit= 0.00379 ft**2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import sqrt\n",
+    "#Initialization of variables\n",
+    "n=1.4\n",
+    "p1=50 #psia\n",
+    "J=778\n",
+    "cp=0.24\n",
+    "T1=520 #R\n",
+    "k=n\n",
+    "R=1545/29\n",
+    "m=1\n",
+    "p2=10 #psia\n",
+    "#calculations\n",
+    "rpt=(2/(n+1))**(n/(n-1))\n",
+    "pt=p1*rpt\n",
+    "Vtrev=223.77*sqrt(cp*T1*(1- rpt**((k-1)/k)))\n",
+    "v1=R*T1/p1/144\n",
+    "vt=v1*(p1/pt)**(1/k)\n",
+    "At=m*vt/Vtrev\n",
+    "V2rev=223.77*sqrt(cp*T1*(1-(p2/p1)**((k-1)/k)))\n",
+    "v2=v1*(p1/p2)**(1/k)\n",
+    "A2=m*v2/V2rev\n",
+    "#results\n",
+    "print \"Area required = %.5f ft**2\"%(At)\n",
+    "print \"\\n Area in case 2 at the exit= %.5f ft**2\"%(A2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.3 Pg:585"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Throat area= 0.0056 ft**2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "J=778\n",
+    "g=32.2\n",
+    "pc=54.6 #psia\n",
+    "h1=1329.1 #Btu/lbm\n",
+    "h2=1265 #btu/lbm\n",
+    "V2rev=1790 #ft/s\n",
+    "cv=0.99\n",
+    "m=1 #lbm\n",
+    "cv2=0.96\n",
+    "#calculations\n",
+    "V2d=cv*V2rev\n",
+    "hd=cv**2 *(h1-h2)\n",
+    "h2d=h1-hd\n",
+    "v2d=9.946\n",
+    "A2d=m*v2d/V2d\n",
+    "#results\n",
+    "print \"Throat area= %.4f ft**2\"%(A2d)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.4 Pg:585"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "average velocity = 31.3 ft/sec\n",
+      "\n",
+      " mass flow rate = 29.0 lbm/sec\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "zm=0.216\n",
+    "pm=62.3 #lbm/ft**2\n",
+    "p1=0.0736 #lbm/ft**2\n",
+    "g=32.2\n",
+    "d=4\n",
+    "#calculations\n",
+    "H=zm*(pm-p1)/12/p1\n",
+    "V=sqrt(2*g*H)\n",
+    "m=pi/4 *d**2 *V*p1\n",
+    "#results\n",
+    "print \"average velocity = %.1f ft/sec\"%(V)\n",
+    "print \"\\n mass flow rate = %.1f lbm/sec\"%(m)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.5 Pg:586"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-17,\n",
+      "Area of throat = 0.00596 ft**2\n",
+      "\n",
+      " Area of exit = 0.00805 ft**2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import sqrt\n",
+    "#Initialization of variables\n",
+    "p0=50 #psia\n",
+    "T0=520 #R\n",
+    "rho0=0.259 #lbm/ft**3\n",
+    "p2=10 #psia\n",
+    "mf=1 #lbm\n",
+    "#calculations\n",
+    "print \"From table B-17,\"\n",
+    "pr=0.528\n",
+    "Tr=0.833\n",
+    "rhor=0.634\n",
+    "ps=pr*p0\n",
+    "Ts=Tr*T0\n",
+    "rhos=rho0*rhor\n",
+    "Vs=49.1*sqrt(Ts)\n",
+    "As=mf/(Vs*rhos)\n",
+    "p2r=p2/p0\n",
+    "M2=1.71\n",
+    "V2=1.487*Vs\n",
+    "T2=0.632*Ts\n",
+    "A2=As*1.35\n",
+    "rho2=rhos*0.317\n",
+    "#results\n",
+    "print \"Area of throat = %.5f ft**2\"%(As)\n",
+    "print \"\\n Area of exit = %.5f ft**2\"%(A2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.6 Pg:587"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Length of pipe = 406.3 ft\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "M1=0.2\n",
+    "M2=0.4\n",
+    "D=0.5  #ft\n",
+    "f=0.015\n",
+    "#calculations\n",
+    "f1=14.5\n",
+    "f2=2.31\n",
+    "dl=(f1-f2)*D/f\n",
+    "#results\n",
+    "print \"Length of pipe = %.1f ft\"%(dl)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.7 Pg:588"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from table B-19\n",
+      "Change in entropy = 0.0224 Btu/lbm R\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "py=20 #psia\n",
+    "px=3.55 #psia\n",
+    "R=1.986/29\n",
+    "#calculations\n",
+    "pr=py/px\n",
+    "print \"from table B-19\"\n",
+    "Mx=2\n",
+    "My=0.577\n",
+    "pr2=0.721\n",
+    "ds=R*log(1/pr2)\n",
+    "#results\n",
+    "print \"Change in entropy = %.4f Btu/lbm R\"%(ds)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.8 Pg:588"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-18 and B-17,\n",
+      "Mach numbers before and after are 1.64 and 0.658 respectively\n",
+      "\n",
+      " Pressure before and after are 11.0 psia and 32.9 psia\n",
+      "\n",
+      " Exhaust pressure = 32.3 psia\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "pi=50 #psia\n",
+    "pe=34.6 #psia\n",
+    "#calculations\n",
+    "print \"From table B-18 and B-17,\"\n",
+    "pr1=1.35\n",
+    "p0f=pi/pr1\n",
+    "pfs=0.528*p0f\n",
+    "per=pe/pfs\n",
+    "Me=0.6\n",
+    "p0e=1.19\n",
+    "pyx=p0e/pr1\n",
+    "Mx=1.64\n",
+    "My=0.658\n",
+    "px=0.22*pi\n",
+    "py=32.9 #psia\n",
+    "p2yx=0.852\n",
+    "pe2=1.65*pfs\n",
+    "#results\n",
+    "print \"Mach numbers before and after are %.2f and %.3f respectively\"%(Mx,My)\n",
+    "print \"\\n Pressure before and after are %.1f psia and %.1f psia\"%(px,py)\n",
+    "print \"\\n Exhaust pressure = %.1f psia\"%(pe2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.9 Pg:589"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-20\n",
+      "Heat required = 272 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "T1=550 #R\n",
+    "T2=2660 #R\n",
+    "ts1=0.207\n",
+    "ts2=0.833\n",
+    "cp=0.24\n",
+    "#calculations\n",
+    "Ts=T1/ts1\n",
+    "Ts0=T2/ts2\n",
+    "print \"From table B-20\"\n",
+    "tr1=0.529\n",
+    "tr2=0.174\n",
+    "dq=cp*Ts0*(tr1-tr2)\n",
+    "#results\n",
+    "print \"Heat required = %d Btu/lbm\"%(dq)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.10 Pg:590"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Internal thrust = 3651 lbf\n",
+      "\n",
+      " Net thrust = 2593 lbf\n",
+      "The answers are a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "M1=0.5\n",
+    "M2=1\n",
+    "A1=0.5 #ft**2\n",
+    "A2=1 #ft**2\n",
+    "p1=14.7 #psia\n",
+    "p2=14.7 #psia\n",
+    "k=1.4\n",
+    "#calculations\n",
+    "thru=p2*144*A2*(1+k*M2**2)-p1*144*A1*(1+k*M1**2)\n",
+    "net=thru-p1*144*(A2-A1)\n",
+    "#results\n",
+    "print \"Internal thrust = %d lbf\"%(thru)\n",
+    "print \"\\n Net thrust = %d lbf\"%(net)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.11 Pg:590"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "mass flow rate = 0.572 lbm/sec\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "p1=50 #psia\n",
+    "pr=0.58\n",
+    "#calculations\n",
+    "p=p1*pr\n",
+    "s1=1.6585\n",
+    "h1=1174.1 #Btu/lbm\n",
+    "sf=0.3680\n",
+    "sfg=1.3313\n",
+    "hfg=945.3\n",
+    "vg=13.746\n",
+    "hf=218.82\n",
+    "x= (s1-sf)/sfg\n",
+    "v2=vg*x\n",
+    "h2=hf+x*hfg\n",
+    "V2rev=223.77*sqrt(h1-h2)\n",
+    "m=pi/4 *1/144 *V2rev/v2\n",
+    "#results\n",
+    "print \"mass flow rate = %.3f lbm/sec\"%(m)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.12 Pg:591"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Mass flow rate = 0.597 lbm/sec\n",
+      "\n",
+      " Meta stable under cooling = 52 F\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "k=1.31\n",
+    "p1=7200 #lbf/ft**2\n",
+    "v1=8.515 #ft**3/lbm\n",
+    "pr=0.6\n",
+    "m1=0.574\n",
+    "T1=741 #R\n",
+    "#calculations\n",
+    "V2rev=8.02*sqrt(k/(k-1) *p1*v1*(1- (pr)**((k-1)/k)))\n",
+    "v2=v1*(1/pr)**(1/k)\n",
+    "m=pi/4 *1/144 *V2rev/v2\n",
+    "C=m/m1\n",
+    "T2=T1*(0.887)\n",
+    "t=250+460 #R\n",
+    "dt=t-T2\n",
+    "#results\n",
+    "print \"Mass flow rate = %.3f lbm/sec\"%(m)\n",
+    "print \"\\n Meta stable under cooling = %d F\"%(dt)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.13 Pg:592"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Area = 1.344 in**2\n",
+      "\n",
+      " diameter = 1.31 in\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "C=0.98\n",
+    "m=1\n",
+    "v=12.55 #ft**3/lbm\n",
+    "V=1372 #ft/s\n",
+    "#calculations\n",
+    "A=m*v/(C*V) *144\n",
+    "D=sqrt(A*4/pi)\n",
+    "#results\n",
+    "print \"Area = %.3f in**2\"%(A)\n",
+    "print \"\\n diameter = %.2f in\"%(D)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.14 Pg:593"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Area = 0.92 in**2\n",
+      "\n",
+      " diameter = 1.080 in\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "nn=0.95\n",
+    "p1=50 #psia\n",
+    "p2=30 #psia\n",
+    "v1=8.515\n",
+    "m=1 #lbm\n",
+    "#calculations\n",
+    "cv=sqrt(nn)\n",
+    "V2rev=1372\n",
+    "V2act=cv*V2rev\n",
+    "n=1.283\n",
+    "v2=v1*(p1/p2)**(1/n)\n",
+    "A=m*v2/V2act *144\n",
+    "D=sqrt(A*4/pi)\n",
+    "#results\n",
+    "print \"Area = %.2f in**2\"%(A)\n",
+    "print \"\\n diameter = %.3f in\"%(D)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.15 Pg:593"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Coefficient of discharge = 0.991 \n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "dFf=110.5 #ft-lbf/lbm\n",
+    "Vd=1028 #ft/s\n",
+    "gc=32.2 #ft/s**2\n",
+    "p0=100 #psia\n",
+    "k=1.4\n",
+    "v0=2.08\n",
+    "p1=55 #psia\n",
+    "p2=99.2 #psia\n",
+    "#calculations\n",
+    "dFe=0.01*Vd**2 /(2*gc)\n",
+    "dF=dFf+dFe\n",
+    "V2ig=(p0*144)**(1/k) *v0/(1-1/k) *((p1*144)**(1-1/k) -(p2*144)**(1-1/k))\n",
+    "C2=(V2ig+dF)/V2ig\n",
+    "C=sqrt(C2)\n",
+    "#results\n",
+    "print \"Coefficient of discharge = %.3f \"%(C)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.16 Pg:594"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Pressure drop in the nozzle = 3.60 lbf/ft**2\n",
+      "\n",
+      " Coefficient of discharge = 0.982 \n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from math import pi,sqrt\n",
+    "#Initialization of variables\n",
+    "dL=1/6 #ft\n",
+    "mf=0.430 #lbm/sec\n",
+    "rho=62.4 \n",
+    "gc=32.2 #ft/s**2\n",
+    "d=0.81/12 #ft\n",
+    "#calculations\n",
+    "V=mf*4/(rho*pi)\n",
+    "VD=V/dL**2\n",
+    "Vd=1.92 #ft/s\n",
+    "dFf=0.031/(2*gc) *2.31\n",
+    "dFe=0.04*Vd**2 /(2*gc)\n",
+    "dF=dFf+dFe\n",
+    "dp=rho*(3.5/(2*gc) +dF)\n",
+    "vd22=(2*gc)/rho *dp /(1-(d/dL)**4)\n",
+    "vd2=sqrt(vd22)\n",
+    "C=Vd/vd2\n",
+    "#results\n",
+    "print \"Pressure drop in the nozzle = %.2f lbf/ft**2\"%(dp)\n",
+    "print \"\\n Coefficient of discharge = %.3f \"%(C)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:13.17 Pg:595"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "mass flow rate = 1.176 lbm/sec\n",
+      "\n",
+      " Coefficient of discharge = 0.598\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "K=0.6003\n",
+    "Y1=0.91\n",
+    "D1=6.065\n",
+    "D2=1.820\n",
+    "rho1=0.156\n",
+    "p1=30\n",
+    "p2=20.18\n",
+    "#calculations\n",
+    "bet=D2/D1\n",
+    "m=0.525*K*Y1 *D2**2 *sqrt(rho1*(p1-p2))\n",
+    "C=K*sqrt(1-bet**4)\n",
+    "#results\n",
+    "print \"mass flow rate = %.3f lbm/sec\"%(m)\n",
+    "print \"\\n Coefficient of discharge = %.3f\"%(C)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch14.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch14.ipynb
new file mode 100644
index 00000000..51e36300
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch14.ipynb
@@ -0,0 +1,602 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 14 Psychrometrics"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.1 Pg:659"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from steam tables,\n",
+      "part a\n",
+      "partial pressure of water = 0.15207 psia\n",
+      "\n",
+      " dew temperature = 46 F\n",
+      "part b\n",
+      "density of water = 0.000474 lbm/ft**3\n",
+      "\n",
+      " in case 2, density of water = 0.000474 lbm/ft**3\n",
+      "\n",
+      " density of air = 0.072765 lbm/ft**3\n",
+      "part c\n",
+      "specific humidity  = 0.0065 lbm steam/lbm air\n",
+      "part d\n",
+      "In method 1, Degree of saturation = 0.293\n",
+      "\n",
+      " In method 2, Degree of saturation = 0.293\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t1=80+460 #R\n",
+    "ps=0.5069 #psia\n",
+    "print \"from steam tables,\"\n",
+    "vs=633.1 #ft**3/lbm\n",
+    "phi=0.3\n",
+    "R=85.6\n",
+    "Ra=53.3\n",
+    "p=14.696\n",
+    "#calculations\n",
+    "tdew=46 #F\n",
+    "pw=phi*ps\n",
+    "rhos=1/vs\n",
+    "rhow=phi*rhos\n",
+    "rhow2= pw*144/(R*t1)\n",
+    "pa=p-pw\n",
+    "rhoa= pa*144/(Ra*t1)\n",
+    "w=rhow/rhoa\n",
+    "mu=phi*(p-ps)/(p-pw)\n",
+    "Ws=0.622*(ps/(p-ps))\n",
+    "mu2=w/Ws\n",
+    "#results\n",
+    "print \"part a\"\n",
+    "print \"partial pressure of water = %.5f psia\"%(pw)\n",
+    "print \"\\n dew temperature = %d F\"%(tdew)\n",
+    "print \"part b\"\n",
+    "print \"density of water = %.6f lbm/ft**3\"%(rhow)\n",
+    "print \"\\n in case 2, density of water = %.6f lbm/ft**3\"%(rhow2)\n",
+    "print \"\\n density of air = %.6f lbm/ft**3\"%(rhoa)\n",
+    "print \"part c\"\n",
+    "print \"specific humidity  = %.4f lbm steam/lbm air\"%(w)\n",
+    "print \"part d\"\n",
+    "print \"In method 1, Degree of saturation = %.3f\"%(mu)\n",
+    "print \"\\n In method 2, Degree of saturation = %.3f\"%(mu2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.2 Pg:659"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "change in moisture content = 0.008857 lbm water/lbm dry air\n",
+      "\n",
+      " in grains, change = 62.00 grains water/lbm dry air\n",
+      "The answers are a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p=14.696 #psia\n",
+    "ps=0.0808  #psia\n",
+    "ps2=0.5069 #psia\n",
+    "phi2=0.5\n",
+    "phi=0.6\n",
+    "grain=7000\n",
+    "#calculations\n",
+    "pw=phi*ps\n",
+    "w1=0.622*pw/(p-pw)\n",
+    "pw2=phi2*ps2\n",
+    "w2=0.622*pw2/(p-pw2)\n",
+    "dw=w2-w1\n",
+    "dwg=dw*grain\n",
+    "#results\n",
+    "print \"change in moisture content = %.6f lbm water/lbm dry air\"%(dw)\n",
+    "print \"\\n in grains, change = %.2f grains water/lbm dry air\"%(dwg)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.3 Pg:660"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "\n",
+      " humidity ratio = 0.0064 lbm/lbm dry air\n",
+      "\n",
+      " relative humidity  = 29.7 percent\n",
+      "\n",
+      " Dew point = 46 F\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t1=80 #F\n",
+    "t2=60 #F\n",
+    "p=14.696 #psia\n",
+    "ps=0.507 #psia\n",
+    "pss=0.256 #psia\n",
+    "cp=0.24\n",
+    "print \"From steam tables,\"\n",
+    "#calculations\n",
+    "ws=0.622*pss/(p-pss)\n",
+    "w=(cp*(t2-t1) + ws*1060)/(1060+ 0.45*(t1-t2))\n",
+    "pw=w*p/(0.622+w)\n",
+    "phi=pw/ps\n",
+    "td=46 #F\n",
+    "#results\n",
+    "print \"\\n humidity ratio = %.4f lbm/lbm dry air\"%(w)\n",
+    "print \"\\n relative humidity  = %.1f percent\"%(phi*100)\n",
+    "print \"\\n Dew point = %d F\"%(td)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.4 Pg:661"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "In case 1, enthalpy = 26.32 Btu/lbm dry air\n",
+      "\n",
+      " In case 1, sigma function = 26.14 Btu/lbm dry air\n",
+      "\n",
+      " In case 2, enthalpy = 26.47 Btu/lbm dry air\n",
+      "\n",
+      " In case 2, sigma function = 26.15 Btu/lbm dry air\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "W=0.0065  #lbm/lbm of dry air\n",
+    "t=80 #F\n",
+    "td=60 #F\n",
+    "#calculations\n",
+    "H=0.24*t+W*(1060+0.45*t)\n",
+    "sig=H-W*(td-32)\n",
+    "Ws=0.0111\n",
+    "H2=0.24*td+Ws*(1060+0.45*td)\n",
+    "sig2=H2-Ws*(td-32)\n",
+    "#results\n",
+    "print \"In case 1, enthalpy = %.2f Btu/lbm dry air\"%(H)\n",
+    "print \"\\n In case 1, sigma function = %.2f Btu/lbm dry air\"%(sig)\n",
+    "print \"\\n In case 2, enthalpy = %.2f Btu/lbm dry air\"%(H2)\n",
+    "print \"\\n In case 2, sigma function = %.2f Btu/lbm dry air\"%(sig2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.5 Pg:662"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "In case 1, Enthalpy = 9.41 Btu/lbm dry air\n",
+      "\n",
+      " In case 2, Enthalpy = 31.15 Btu/lbm dry air\n",
+      "\n",
+      " Heat added = 21.49 Btu/lbm dry air\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t1=30 #F\n",
+    "t2=60 #F\n",
+    "t3=80 #F\n",
+    "W1=0.00206\n",
+    "W2=0.01090\n",
+    "#calculations\n",
+    "cm1=0.24+0.45*W1\n",
+    "H1=cm1*t1+W1*1060\n",
+    "cm2=0.24+0.45*W2\n",
+    "H2=cm2*t3+W2*1060\n",
+    "hf=t2-32\n",
+    "dq=H2-H1-(W2-W1)*hf\n",
+    "#results\n",
+    "print \"In case 1, Enthalpy = %.2f Btu/lbm dry air\"%(H1)\n",
+    "print \"\\n In case 2, Enthalpy = %.2f Btu/lbm dry air\"%(H2)\n",
+    "print \"\\n Heat added = %.2f Btu/lbm dry air\"%(dq)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.6 Pg:663"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "using psychrometric charts,\n",
+      "part a\n",
+      "partial pressure of water = 0.15 psia\n",
+      "\n",
+      " dew temperature = 46 F\n",
+      "part b\n",
+      "density of water = 0.000000 lbm/ft**3\n",
+      "\n",
+      " density of air = 0.0728 lbm/ft**3\n",
+      "part c\n",
+      "specific humidity  = 0.00657 lbm water/lbm air\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "pw=0.15#psia\n",
+    "print \"using psychrometric charts,\"\n",
+    "tdew=46 #F\n",
+    "#calculations\n",
+    "va=13.74 #ft**3/lbm dry air\n",
+    "rhoa=1/va\n",
+    "V=13.74\n",
+    "mw=46/7000\n",
+    "rhow=mw/V\n",
+    "w=0.00657\n",
+    "#results\n",
+    "print \"part a\"\n",
+    "print \"partial pressure of water = %.2f psia\"%(pw)\n",
+    "print \"\\n dew temperature = %d F\"%(tdew)\n",
+    "print \"part b\"\n",
+    "print \"density of water = %.6f lbm/ft**3\"%(rhow)\n",
+    "print \"\\n density of air = %.4f lbm/ft**3\"%(rhoa)\n",
+    "print \"part c\"\n",
+    "print \"specific humidity  = %.5f lbm water/lbm air\"%(w)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.7 Pg:664"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From humidity charts,\n",
+      "Enthalpy change = 21.53 Btu/lbm dry air\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "W1=0.00206 #lbm/lbm dry air\n",
+    "W2=0.01090 #lbm/lbm dry air\n",
+    "t=60 #F\n",
+    "print \"From humidity charts,\"\n",
+    "#calculations\n",
+    "dw=W1-W2\n",
+    "hs=144.4\n",
+    "hs2=66.8-32\n",
+    "w1=14.4 #Btu/lbm\n",
+    "ws1=20 #Btu/lbm\n",
+    "w2=76.3 #Btu/lbm\n",
+    "ws2=98.5 #Btu/lbm\n",
+    "dwh1=-(w1-ws1)/7000 *hs\n",
+    "H1=9.3+dwh1\n",
+    "dwh2=(w2-ws2)/7000 *hs2\n",
+    "H2=31.3+dwh2\n",
+    "dwc=dw*(t-32)\n",
+    "dq=H2-H1+dwc\n",
+    "#results\n",
+    "print \"Enthalpy change = %.2f Btu/lbm dry air\"%(dq)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.8 Pg:665"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From psychrometric charts at 50 F and 80 F,\n",
+      "The two initial states have been multiplied by 108/262 and distance 2-3 is located\n",
+      "humidity = 0.83 \n",
+      "\n",
+      " Temperature = 62.5 F\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "print \"From psychrometric charts at 50 F and 80 F,\"\n",
+    "va1=13 #ft**3/lbm dry air\n",
+    "va2=13.88 #ft**3/lbm dry air\n",
+    "flow=2000 #cfm\n",
+    "#calculations\n",
+    "ma1= flow/va1\n",
+    "ma2=flow/va2\n",
+    "print \"The two initial states have been multiplied by 108/262 and distance 2-3 is located\"\n",
+    "t=62.5# F\n",
+    "phi=0.83 #percent\n",
+    "#results\n",
+    "print \"humidity = %.2f \"%(phi)\n",
+    "print \"\\n Temperature = %.1f F\"%(t)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.9 Pg:666"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from psychrometric charts,\n",
+      "Dry bulb temperature = 71.76 F\n",
+      "\n",
+      " percent humidity  = 0.80\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t=90 #F\n",
+    "ts=67.2 #F\n",
+    "phi=0.3\n",
+    "per=0.8\n",
+    "#calculations\n",
+    "dep=t-ts\n",
+    "dt=dep*per\n",
+    "tf=t-dt\n",
+    "print \"from psychrometric charts,\"\n",
+    "phi2=0.8\n",
+    "#results\n",
+    "print \"Dry bulb temperature = %.2f F\"%(tf)\n",
+    "print \"\\n percent humidity  = %.2f\"%(phi2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.10 Pg:667"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From psychrometric charts,\n",
+      "cooling range = 25 F\n",
+      "\n",
+      " Approach = 10 F\n",
+      "\n",
+      " amount of water cooled per pound of dry air = 1.216 lbm dry air/lbm dry air\n",
+      "\n",
+      " percentage of water lost by evaporation = 2.12 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m=1 #lbm\n",
+    "t1=100 #F\n",
+    "t2=75 #F\n",
+    "db=65 #F\n",
+    "print \"From psychrometric charts,\"\n",
+    "t11=82 #F\n",
+    "phi1=0.4\n",
+    "H1=30 #Btu/lbm dry air\n",
+    "w1=65 #grains/lbm dry air\n",
+    "w2=250 #grains/lbm dry air\n",
+    "#calculations\n",
+    "cr=t1-t2\n",
+    "appr=t2-db\n",
+    "dmf3=(w2-w1)*0.0001427\n",
+    "hf3=68\n",
+    "hf4=43\n",
+    "H2=62.2\n",
+    "H1=30\n",
+    "mf4= (H1-H2+ dmf3*hf3)/(hf4-hf3)\n",
+    "per=dmf3/(dmf3+mf4)\n",
+    "#results\n",
+    "print \"cooling range = %d F\"%(cr)\n",
+    "print \"\\n Approach = %d F\"%(appr)\n",
+    "print \"\\n amount of water cooled per pound of dry air = %.3f lbm dry air/lbm dry air\"%(mf4)\n",
+    "print \"\\n percentage of water lost by evaporation = %.2f percent\"%(per*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:14.11 Pg:668"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "flow rate of air = 449820 lbm/hr.It is equal to 99960 cfm\n",
+      "\n",
+      " Total heat transferred = 13494600 Btu/hr\n",
+      "\n",
+      " Enthalpy = 30.0 Btu/lbm dry air\n",
+      "\n",
+      " Using second method, Enthalpy = 30.0 Btu/lbm\n",
+      "\n",
+      " Performance factor = 3.309 \n",
+      "\n",
+      " logrithamic mean enthalpy difference = 2.48 . Estimated low percentage = 25 low\n",
+      "The answers are a bit different due to rounding off error in textbook.\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "mfr=1\n",
+    "water=900 #gallons\n",
+    "t2=110 #F\n",
+    "t1=80 #F\n",
+    "cp1=1\n",
+    "#calculations\n",
+    "mfa=mfr*water*8.33*60\n",
+    "mfc=mfa/(60*0.075)\n",
+    "qa=mfa*(t2-t1)\n",
+    "dH=qa/(mfc*4.5)\n",
+    "dH2=mfr*cp1*(t2-t1)\n",
+    "H1=23.73\n",
+    "H2=5.08\n",
+    "f=3.309\n",
+    "lnmean=(H1-H2)/log(H1/H2)\n",
+    "dtt=(t2-t1)/lnmean\n",
+    "per=25\n",
+    "#results\n",
+    "print \"flow rate of air = %d lbm/hr.It is equal to %d cfm\"%(mfa,mfc)\n",
+    "print \"\\n Total heat transferred = %d Btu/hr\"%(qa)\n",
+    "print \"\\n Enthalpy = %.1f Btu/lbm dry air\"%(dH)\n",
+    "print \"\\n Using second method, Enthalpy = %.1f Btu/lbm\"%(dH2)\n",
+    "print \"\\n Performance factor = %.3f \"%(f)\n",
+    "print \"\\n logrithamic mean enthalpy difference = %.2f . Estimated low percentage = %d low\"%(dtt,per)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook.\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch15.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch15.ipynb
new file mode 100644
index 00000000..0309850b
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch15.ipynb
@@ -0,0 +1,349 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 15 Vapor cycle and processes"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.1 Pg:697"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from steam tables,\n",
+      "Thermal efficiency = 45 percent\n",
+      "\n",
+      " Furnace efficiency = 33.8 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p1=600 #psia\n",
+    "p2=0.2563 #psia\n",
+    "t1=486.21 #F\n",
+    "t2=60 #F\n",
+    "fur=0.75\n",
+    "#calculations\n",
+    "print \"from steam tables,\"\n",
+    "h1=1203.2\n",
+    "hf1=471.6\n",
+    "hfg1=731.6\n",
+    "h2=1088\n",
+    "hf2=28.06\n",
+    "hfg2=1059.9\n",
+    "s1=1.4454\n",
+    "sf1=0.6720\n",
+    "sfg1=0.7734\n",
+    "s2=2.0948\n",
+    "sf2=0.0555\n",
+    "sfg2=2.0393\n",
+    "xd=(s1-sf2)/sfg2\n",
+    "hd=hf2+xd*hfg2\n",
+    "xa=0.3023\n",
+    "ha=hf2+xa*hfg2\n",
+    "wbc=0\n",
+    "wda=0\n",
+    "wcd=h1-hd\n",
+    "wab=ha-hf1\n",
+    "W=wab+wcd+wbc+wda\n",
+    "Wrev=hfg1- (t2+459.7)*sfg1\n",
+    "etat=(t1-t2)/(t1+459.7)\n",
+    "eta=fur*etat\n",
+    "#results\n",
+    "print \"Thermal efficiency = %d percent\"%(etat*100)\n",
+    "print \"\\n Furnace efficiency = %.1f percent\"%(eta*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.2 Pg:698"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Thermal efficiency = 22.8 percent\n",
+      "\n",
+      " Overall efficiency = 17.1 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "dhab=-123.1\n",
+    "etac=0.5\n",
+    "ha=348.5\n",
+    "etaf=0.75\n",
+    "eta=0.85\n",
+    "hf=471.6\n",
+    "hfg=731.6\n",
+    "hc=1203.2\n",
+    "dhcd=452.7\n",
+    "#calculations\n",
+    "dwabs=dhab/etac\n",
+    "hbd=ha-dwabs\n",
+    "dwcds=dhcd*eta\n",
+    "dqa=hc-hbd\n",
+    "etat=(dwcds+dwabs)/dqa\n",
+    "eta=etat*etaf\n",
+    "#results\n",
+    "print \"Thermal efficiency = %.1f percent\"%(etat*100)\n",
+    "print \"\\n Overall efficiency = %.1f percent\"%(eta*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.3 Pg:699"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "Thermal efficiency = 38.4 percent\n",
+      "\n",
+      " Overall efficiency = 32.7 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "t=60 #F\n",
+    "J=778.16\n",
+    "p1=600 #psia\n",
+    "p2=0.2563 #psia\n",
+    "etaf=0.85 \n",
+    "#calculations\n",
+    "print \"From steam tables,\"\n",
+    "vf=0.01604 #ft**3/lbm\n",
+    "dw=-vf*(p1-p2)*144/J\n",
+    "ha=28.06 #Btu/lbm\n",
+    "hb=29.84 #Btu/lbm\n",
+    "hd=1203.2 #Btu/lbm\n",
+    "he=750.5 #Btu/lbm\n",
+    "dqa=hd-hb\n",
+    "dqr=ha-he\n",
+    "dw=dqa+dqr\n",
+    "dwturb=hd-he\n",
+    "dwpump=ha-hb\n",
+    "etat=dw/dqa\n",
+    "eta=etat*etaf\n",
+    "#results\n",
+    "print \"Thermal efficiency = %.1f percent\"%(etat*100)\n",
+    "print \"\\n Overall efficiency = %.1f percent\"%(eta*100)\n",
+    "    "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.4 Pg:699"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Thermal efficiency = 32.5 percent\n",
+      "\n",
+      " Overall efficiency = 27.7 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "dhab=-1.78\n",
+    "etac=0.5\n",
+    "ha=28.06\n",
+    "eta=0.85\n",
+    "hf=471.6\n",
+    "hfg=731.6\n",
+    "hd=1203.2\n",
+    "dhcd=452.7\n",
+    "#calculations\n",
+    "dwabs=dhab/etac\n",
+    "hbd=ha-dwabs\n",
+    "dwcds=dhcd*eta\n",
+    "dqa=hd-hbd\n",
+    "etat=(dwcds+dwabs)/dqa\n",
+    "eta=etat*eta\n",
+    "#results\n",
+    "print \"Thermal efficiency = %.1f percent\"%(etat*100)\n",
+    "print \"\\n Overall efficiency = %.1f percent\"%(eta*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.5 Pg:700"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Thermal efficiency in case 1= 46.5 percent\n",
+      "\n",
+      " Thermal efficiency in case 1= 40.9 percent\n",
+      "\n",
+      " High pressure work = 187.8 Btu/lbm\n",
+      "\n",
+      " Low pressure work = 451.5 Btu/lbm\n",
+      "\n",
+      " Net work = 639.3 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "sh=1.6070\n",
+    "ph=94.8 #psia\n",
+    "th=324 #F\n",
+    "tr=60 #F\n",
+    "hh=1186.2 \n",
+    "pi=94.8 #psia\n",
+    "hi=1399.5\n",
+    "si=1.8265\n",
+    "#calculations\n",
+    "Q=hi-hh\n",
+    "Hr=-(tr+459.7)*(si-sh)\n",
+    "work= Q+Hr\n",
+    "eff=work/Q\n",
+    "Qa1=1557.5\n",
+    "W1=637.1 \n",
+    "etat=W1/Qa1\n",
+    "he=1374\n",
+    "hj=948\n",
+    "Whp=he-hh\n",
+    "Wlp=hi-hj\n",
+    "Wnet=Whp+Wlp\n",
+    "#results\n",
+    "print \"Thermal efficiency in case 1= %.1f percent\"%(eff*100)\n",
+    "print \"\\n Thermal efficiency in case 1= %.1f percent\"%(etat*100)\n",
+    "print \"\\n High pressure work = %.1f Btu/lbm\"%(Whp)\n",
+    "print \"\\n Low pressure work = %.1f Btu/lbm\"%(Wlp)\n",
+    "print \"\\n Net work = %.1f Btu/lbm\"%(Wnet)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:15.6 Pg:701"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "thermal efficiency = 42.6 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p2=600 #psia\n",
+    "p1=44 #psia\n",
+    "te=486.21 #F\n",
+    "tb=273.1 #F\n",
+    "J=778.16\n",
+    "p3=0.25 #psia\n",
+    "#calculations\n",
+    "hc=241.9\n",
+    "hj=834.6\n",
+    "y=1-0.805\n",
+    "v1=0.0172\n",
+    "v2=0.016\n",
+    "ha=28.06\n",
+    "hd=hc+v1*(p2-p1)*144/J\n",
+    "hb=ha+v2*(p1-p3)*144/J\n",
+    "hh=1374\n",
+    "Qa=hh-hd\n",
+    "Qr=(ha-hj)*(1-y)\n",
+    "etat=(Qa+Qr)/Qa\n",
+    "#results\n",
+    "print \"thermal efficiency = %.1f percent\"%(etat*100)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch16.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch16.ipynb
new file mode 100644
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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 16 Combustion"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.1 Pg:738"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Molecule is C7 H17\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "per=85\n",
+    "#calculations\n",
+    "a=per/12\n",
+    "b=100-per\n",
+    "ad=1.13*a\n",
+    "bd=1.13*b\n",
+    "#results\n",
+    "print \"Molecule is C%d H%d\"%(ad,bd+1)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.2 Pg:738"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Oxygen = 8.74 and Nitrogen = 32.90\n",
+      "\n",
+      "Equation is C7.333 H6 + 8.74 O2 + 32.85 N2 = 7.333 CO2 + 3 H2O + 0.03120 SO2 + 32.90 N2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "per=0.071 #mass fraction of nitrogen\n",
+    "#calculations\n",
+    "O2=8.74\n",
+    "N2=per/2 + 3.76*O2\n",
+    "Nin=32.85\n",
+    "CO2=7.333\n",
+    "H2o=3\n",
+    "So2=0.0312\n",
+    "#results\n",
+    "print \"Oxygen = %.2f and Nitrogen = %.2f\"%(O2,N2)\n",
+    "print \"\\nEquation is C%.3f H%d + %.2f O2 + %.2f N2 = %.3f CO2 + %d H2O + %.5f SO2 + %.2f N2\"%(CO2,2*H2o,O2,Nin,CO2,H2o,So2,N2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.3 Pg:739"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 12.06 lbm air/lbm fuel\n",
+      "\n",
+      "In dry air, Air-fuel ratio = 9.9 lbm air/lbm fuel as fired\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "M=29\n",
+    "m1=8.74\n",
+    "m2=32.85\n",
+    "fuel=100 #lbm\n",
+    "#calculations\n",
+    "mass=M*(m1+m2)\n",
+    "AF=mass/fuel\n",
+    "a2=9.75\n",
+    "b2=12.19\n",
+    "AF2=mass/(fuel+a2+b2)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.2f lbm air/lbm fuel\"%(AF)\n",
+    "print \"\\nIn dry air, Air-fuel ratio = %.1f lbm air/lbm fuel as fired\"%(AF2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.4 Pg:740"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Mass of dry flue gases = 12.50 lbm dry flue gas/lbm fuel ash and moisture free\n",
+      "\n",
+      " Mass of dry flue gases = 10.25 lbm dry flue gas/lbm fuel as fired \n",
+      "\n",
+      " Energy carried away = 187079.8 btu/mol coal as fired which is same as  = 1534.2 Btu/lbm mol coal \n",
+      "The answers are a bit different due to rounding off errors in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m1=322.3 #Mass of Co2\n",
+    "m2=2 #Mass of SO2\n",
+    "m3=926 #Mass of N2\n",
+    "basis=121.94 #Basis taken\n",
+    "#calculations\n",
+    "m=m1+m2+m3\n",
+    "ratio=m/basis\n",
+    "dh=5777 #Btu/mol\n",
+    "h1=dh*7.364\n",
+    "h2=14037\n",
+    "h3=130501\n",
+    "H=h1+h2+h3\n",
+    "hrat=H/basis\n",
+    "#results\n",
+    "print \"Mass of dry flue gases = %.2f lbm dry flue gas/lbm fuel ash and moisture free\"%(m/100)\n",
+    "print \"\\n Mass of dry flue gases = %.2f lbm dry flue gas/lbm fuel as fired \"%(ratio)\n",
+    "print \"\\n Energy carried away = %.1f btu/mol coal as fired which is same as  = %.1f Btu/lbm mol coal \"%(H, hrat)\n",
+    "print \"The answers are a bit different due to rounding off errors in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.6 Pg:741"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Final orsat composition is 1 CO2 + 0.22 H20 + 7.52 N2\n",
+      "\n",
+      " Percentage of co2 on a wet basis = 11.4 percent\n",
+      "\n",
+      " percentage of co2 on a dry basis = 11.74 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p=14.7 #psia\n",
+    "ps=0.363 #psia\n",
+    "n2=7.52 #moles\n",
+    "n1=1 #moles\n",
+    "#calculations\n",
+    "x= (n1+n2)*ps/p /(1-ps/p)\n",
+    "n=n1+n2+x\n",
+    "y1=n1/n\n",
+    "y2=n1/(n1+n2)\n",
+    "#results\n",
+    "print \"Final orsat composition is %d CO2 + %.2f H20 + %.2f N2\"%(n1, x, n2)\n",
+    "print \"\\n Percentage of co2 on a wet basis = %.1f percent\"%(y1*100)\n",
+    "print \"\\n percentage of co2 on a dry basis = %.2f percent\"%(y2*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.7 Pg:742"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 11.3 lbm air/lbm fuel\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "N2=78.1\n",
+    "M=29\n",
+    "co2=8.7\n",
+    "co=8.9\n",
+    "x4=0.3\n",
+    "x5=3.7\n",
+    "x6=14.7\n",
+    "#calculations\n",
+    "O2=N2/3.76\n",
+    "Z=(co2+co+x4)/8\n",
+    "AF=(O2+N2)*M/(Z*113)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.1f lbm air/lbm fuel\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.8 Pg:743"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 10.2 lbm air/lbm fuel as fired\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "basis=100 #lbm\n",
+    "x1=0.6\n",
+    "ash=12 #lbm\n",
+    "N2=79.7\n",
+    "M=29\n",
+    "#calculations\n",
+    "x=ash/x1\n",
+    "C=(1-x1)*x\n",
+    "O2=N2/3.76\n",
+    "a= (14.6+0.2)/(5.83-0.66)\n",
+    "AF=(O2+N2)*M/(a*100)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.1f lbm air/lbm fuel as fired\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.9 Pg:744"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 11.4 lbm air/lbm fuel\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "N2=78.1 #Moles of Nitrogen\n",
+    "M=29 #Molar mass of Air\n",
+    "ba=2.12 #Basis\n",
+    "x4=0.3 #Moles of Ch4\n",
+    "x5=3.7 #Moles of H2\n",
+    "x6=14.7 #moles of H2o\n",
+    "#calculations\n",
+    "O2=N2/3.76\n",
+    "O2=N2/3.76\n",
+    "Z=(x4*4+x5*2+x6*2)/17\n",
+    "AF=(O2+N2)*M/(Z*113)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.1f lbm air/lbm fuel\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.10 Pg:745"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 11.3 lbm air/lbm fuel\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "N2=78.1 #Moles of Nitrogen\n",
+    "M=29 #Molar mass of Air\n",
+    "ba=2.12 #Basis\n",
+    "x4=0.3 #Moles of Ch4\n",
+    "x5=3.7 #Moles of H2\n",
+    "x6=14.7 #moles of H2o\n",
+    "#calculations\n",
+    "O2=N2/3.76\n",
+    "c=14.7\n",
+    "b= x4*4 + x5*2 + x6*2\n",
+    "a=b/ba\n",
+    "AF=(O2+N2)*M/(a*12 + b)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.1f lbm air/lbm fuel\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.11 Pg:746"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 11.3 lbm air/lbm fuel\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "co2=8.7 #Moles of CO2\n",
+    "co=8.9 #Moles of CO\n",
+    "N2=78.1 #Moles of Nitrogen\n",
+    "M=29 #Molar mass of Air\n",
+    "ba=2.12 #Basis\n",
+    "x4=0.3 #Moles of Ch4\n",
+    "x5=3.7 #Moles of H2\n",
+    "x6=14.7 #moles of H2o\n",
+    "#calculations\n",
+    "O2=N2/3.76\n",
+    "c=14.7\n",
+    "Z=2.238\n",
+    "X=(Z*17-x4*4-x5*2)/2\n",
+    "a=co2+co/2+x4+x6/2\n",
+    "b=3.764*a\n",
+    "AF=(O2+N2)*M/(Z*113)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.1f lbm air/lbm fuel\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.12 Pg:747"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Air fuel ratio = 11.37\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "x1=8.7 #Moles of Co2\n",
+    "x2=8.9 #Moles of CO\n",
+    "x3=0.3 #Moles of O2\n",
+    "N=78.1 #Moles of N2\n",
+    "z=113 #Af factor\n",
+    "M=29 #Molar mass of air\n",
+    "#calculations\n",
+    "co2=(x1+x2+x3)*100/(N+x1+x2+x3)\n",
+    "a=2.325\n",
+    "AF=103*M/(a*z)\n",
+    "#results\n",
+    "print \"Air fuel ratio = %.2f\"%(AF)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.13 Pg:748"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 17,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Nitrogen = 87.1 percent\n",
+      "\n",
+      "Equation is a(96 CH4 + 3 H2+ 1 CO) + 87.1/3.76 O2 + 87.1 N2 = 10.8 CO2 + 1.2 CO + 0.6 H2 + 0.3 CH4 + 87.1 N2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "co=1.2 #Moles of CO\n",
+    "co2=10.8 #Moles of CO2\n",
+    "#calculations\n",
+    "H2=co/2\n",
+    "ch4=0.3\n",
+    "N2=88-H2-ch4\n",
+    "#results\n",
+    "print \"Nitrogen = %.1f percent\"%(N2)\n",
+    "print \"\\nEquation is a(96 CH4 + 3 H2+ 1 CO) + %.1f/3.76 O2 + %.1f N2 = %.1f CO2 + %.1f CO + %.1f H2 + %.1f CH4 + %.1f N2\"%(N2,N2,co2,co,H2,ch4,N2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.14 Pg:748"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 18,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Higher heating value = -2363996 Btu\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "dH=-2369859 #Btu\n",
+    "r=1.986 #Gas constant\n",
+    "dn=5.5 #Change in number of moles\n",
+    "T=536.7 #R\n",
+    "#calculations\n",
+    "dQ=dH+dn*r*T\n",
+    "#results\n",
+    "print \"Higher heating value = %d Btu\"%(dQ)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.15 Pg:749"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 19,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from steam tables,\n",
+      "Lower heating value = -2203398 Btu/lbm\n",
+      "The answers are a bit different due to rounding off error in textbook.\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "M2=18 #Molar mass of water\n",
+    "M=170 #Molar mass of octane\n",
+    "p=0.4593 #Pressure of octane #psia\n",
+    "print \"from steam tables,\"\n",
+    "vfg=694.9 \n",
+    "J=778.2\n",
+    "m=9*18 #Mass of water\n",
+    "u1=-2363996 #Btu\n",
+    "#calculations\n",
+    "hfg=1050.4 #Btu/lbm\n",
+    "ufg= hfg- p*vfg*144/J\n",
+    "dU=ufg*m \n",
+    "Lhv=u1+dU\n",
+    "#results\n",
+    "print \"Lower heating value = %d Btu/lbm\"%(Lhv)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.16 Pg:750"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From Table B-10,\n",
+      "Heat of reaction = -2202154 Btu\n",
+      "The answers are a bit different due to rounding off error in textbook.\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "n1=8 #Moles of CO2\n",
+    "n2=9 #Moles of H2O\n",
+    "n3=1 #Moles of Octane\n",
+    "n4=12.5 #Moles of Oxygen\n",
+    "print \"From Table B-10,\"\n",
+    "U11=3852 #Internal energy at 1000 R of CO2\n",
+    "U12=115 #Internal energy at 537 R of CO2\n",
+    "U21=3009 #Internal energy at 1000 R of H2O\n",
+    "U22=101 #Internal energy at  537 R of H2O\n",
+    "U31=24773 #Internal energy at 1000 R of Octane\n",
+    "U32=640 #Internal energy at 537 R of Octane\n",
+    "U41=2539 #Internal energy at 1000 R of Oxygen\n",
+    "U42=83 #Internal energy at 537 R of Oxygen\n",
+    "H=-2203389 #heat Btu\n",
+    "#calculations\n",
+    "dU1=n1*(U11-U12)+n2*(U21-U22)\n",
+    "dU2=n3*(U31-U32)+n4*(U41-U42)\n",
+    "Q=H+dU1-dU2\n",
+    "#results\n",
+    "print \"Heat of reaction = %d Btu\"%(Q)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.17 Pg:751"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from table B-10,\n",
+      "Upon interpolating, T2 = 5271 R\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "n1=8 #Moles of CO2\n",
+    "n2=9 #Moles of H2O\n",
+    "n3=47 #Moles of N2\n",
+    "print \"from table B-10,\"\n",
+    "h1=118 #Enthalpy of CO2\n",
+    "h2=104 #Enthalpy of H2O\n",
+    "h3=82.5 #Enthalpy of N2\n",
+    "Q=2203279 #Btu\n",
+    "#calculations\n",
+    "U11=n1*h1+n2*h2+n3*h3\n",
+    "U12=U11+Q\n",
+    "T2=5271 #R\n",
+    "#results\n",
+    "print \"Upon interpolating, T2 = %d R\"%(T2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.18 Pg:752"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 23,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "In case 1, Equilibrium constant = 38.5 \n",
+      "\n",
+      "In case 2, Equilibrium constant = 1480.1 \n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "n1=0.95\n",
+    "n2=0.05\n",
+    "n3=0.025\n",
+    "P=147 #psia\n",
+    "pa=14.7 #psia\n",
+    "#calculations\n",
+    "n=n1+n2+n3\n",
+    "p1=n1/n *P/pa\n",
+    "p2=n2/n *P/pa\n",
+    "p3=n3/n *P/pa\n",
+    "Kp1= p1/(p2*p3**0.5)\n",
+    "Kp2= p1**2 /(p2**2 *p3)\n",
+    "#results\n",
+    "print \"In case 1, Equilibrium constant = %.1f \"%(Kp1)\n",
+    "print \"\\nIn case 2, Equilibrium constant = %.1f \"%(Kp2)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:16.19 Pg:753"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 38,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "percentage of dissociation = 34.3 percent\n",
+      "\n",
+      " If pressure =10 . Degree of dissociation = 18 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "from sympy.abc import x,y\n",
+    "from sympy import solve,N\n",
+    "#Initialization of variables\n",
+    "kp=5 \n",
+    "#calculations\n",
+    "vec=solve(24*x**3 + 3*x-2,x)\n",
+    "x=N(vec[2],6)\n",
+    "vec2=solve(249*y**3 +3*y-2,y)\n",
+    "y=N(vec2[2],6)\n",
+    "#results\n",
+    "print \"percentage of dissociation = %.1f percent\"%(x*100)\n",
+    "print \"\\n If pressure =10 . Degree of dissociation = %d percent\"%(y*100)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Ex:16.20 Pg:754"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 41,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Extent of reaction= 78 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "from sympy.abc import x,y\n",
+    "from sympy import solve,N\n",
+    "\n",
+    "#Initialization of variables\n",
+    "vec=solve(24*x**3 +48*x**2 + 7*x -4,x)\n",
+    "x=N(vec[1],6) *100\n",
+    "#results\n",
+    "print \"Extent of reaction= %d percent\"%(100-x)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch17.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch17.ipynb
new file mode 100644
index 00000000..9b54ad03
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch17.ipynb
@@ -0,0 +1,87 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 17 Gas cycles and processes"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:17.1 Pg:768"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\n",
+      " Thermal efficiency = 14.9 percent\n",
+      "\n",
+      " Moles of fuel burned per mol of air = 0.00177 mol fuel/mol air\n",
+      "\n",
+      " Mass ratio in pounds = 0.00866 lbm fuel/lbm air\n",
+      "\n",
+      " Air fuel ratio = 115 lbm air/lbm fuel\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "\n",
+    "#Initialization of variables\n",
+    "ha=1033 #Btu/mol air\n",
+    "hbd=2992 #Btu/mol air\n",
+    "hc=7823 #Btu/mol air\n",
+    "hdd=5142 #Btu/mol air\n",
+    "Hv=2733000 #Btu/mol\n",
+    "M=29\n",
+    "#calculations\n",
+    "Wt=hc-hdd\n",
+    "Wc=ha-hbd\n",
+    "Net=Wt+Wc\n",
+    "Heat=hc-hbd\n",
+    "etat=Net*100/Heat\n",
+    "molair=Heat/Hv\n",
+    "mr=molair*142/M\n",
+    "Af=1/mr\n",
+    "#results\n",
+    "print \"\\n Thermal efficiency = %.1f percent\"%(etat)\n",
+    "print \"\\n Moles of fuel burned per mol of air = %.5f mol fuel/mol air\"%(molair)\n",
+    "print \"\\n Mass ratio in pounds = %.5f lbm fuel/lbm air\"%(mr)\n",
+    "print \"\\n Air fuel ratio = %d lbm air/lbm fuel\"%(Af)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch2.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch2.ipynb
new file mode 100644
index 00000000..30c440b6
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch2.ipynb
@@ -0,0 +1,107 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 2 Fundamental Concepts"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:2.1 Pg:34"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Potential energy = 3217.39 ft-lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "z=100 #ft\n",
+    "m=32.1739 #lbm\n",
+    "#calculations\n",
+    "PE=m*z\n",
+    "#results\n",
+    "print \"Potential energy = %.2f ft-lbm\"%(PE)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:2.2 Pg:35"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Absolute energy of this mixture = 5.40e+17 ft-lbf\n",
+      "\n",
+      " In case b, there is no change in mass\n",
+      "\n",
+      " Change in mass = -3.15e-09 lbm\n",
+      "The answers are a bit different due to rounding off error in textbook.\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m0=18.016 #lbm\n",
+    "gc=32.1739 #lbm ft/lbf sec**2\n",
+    "c=186000*5280\n",
+    "dU=94.4*10**6 #ft-lbf\n",
+    "#calculations\n",
+    "U=m0/gc *c**2\n",
+    "dm= -dU*gc/c**2\n",
+    "#results\n",
+    "print \"Absolute energy of this mixture = %.2e ft-lbf\"%(U)\n",
+    "print \"\\n In case b, there is no change in mass\"\n",
+    "print \"\\n Change in mass = %.2e lbm\"%(dm)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook.\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch3.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch3.ipynb
new file mode 100644
index 00000000..9ac141c2
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch3.ipynb
@@ -0,0 +1,100 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 3 Temperature and the ideal gas"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:3.2 Pg:59 "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Volume = 379.5 ft**3/mol\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p=14.7 #psia\n",
+    "R0=1545 \n",
+    "t=460 +60 #R\n",
+    "#calculations\n",
+    "v=R0*t/(p*144)\n",
+    "#results\n",
+    "print \"Volume = %.1f ft**3/mol\"%(v)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:3.3 Pg:59"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "density of nitrogen = 0.0932 lbm/ft**3\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "p=20.0 #psia\n",
+    "R0=1545.0 \n",
+    "t=460 +100 #R\n",
+    "M=28\n",
+    "#calculations\n",
+    "v=R0*t/(p*144*M)\n",
+    "rho=1/v\n",
+    "#results\n",
+    "print \"density of nitrogen = %.4f lbm/ft**3\"%(rho)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch5.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch5.ipynb
new file mode 100644
index 00000000..576e9b60
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch5.ipynb
@@ -0,0 +1,149 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 5 The first law and the dynamic open system"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:5.2 Pg:105"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "work done by the system = -9.7 Btu/lbm\n",
+      "\n",
+      " Power = -48.6 Btu/s\n"
+     ]
+    }
+   ],
+   "source": [
+    "## Initialization of variables\n",
+    "rate= 5 #lbm/sec\n",
+    "Q=50 #Btu/s\n",
+    "h2=1020 #Btu/lbm\n",
+    "h1=1000 #Btu/lbm\n",
+    "V2=50 #ft/s\n",
+    "V1=100 #ft/s\n",
+    "J=778\n",
+    "g=32.2 #ft/s**2\n",
+    "gc=g\n",
+    "Z2=0\n",
+    "Z1=100 #ft\n",
+    "#calculations\n",
+    "dw=Q/rate -(h2-h1) -(V2**2- V1**2)/(2*gc*J) -g/gc *(Z2-Z1)/J\n",
+    "power=dw*rate\n",
+    "#results\n",
+    "print \"work done by the system = %.1f Btu/lbm\"%(dw)\n",
+    "print \"\\n Power = %.1f Btu/s\"%(power)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:5.3 Pg:106"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Area of inlet pipe = 0.75 ft**2\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "V=100.0 #ft/s\n",
+    "v=15 #lbm/ft**3\n",
+    "m=5 #lbm/s\n",
+    "#calculations\n",
+    "A=m*v/V\n",
+    "#results\n",
+    "print \"Area of inlet pipe = %.2f ft**2\"%(A)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:5.4 Pg:106"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-4\n",
+      "Final temperature of the steam = 540 F\n",
+      "\n",
+      " Change in temperature = 212 F\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P=100.0 #psia\n",
+    "#calculations\n",
+    "print \"From table B-4\"\n",
+    "h=1187.2 #Btu/lbm\n",
+    "t1=328 #F\n",
+    "t2=540 #F\n",
+    "dt=t2-t1\n",
+    "#results\n",
+    "print \"Final temperature of the steam = %d F\"%(t2)\n",
+    "print \"\\n Change in temperature = %d F\"%(dt)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch7.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch7.ipynb
new file mode 100644
index 00000000..54e86231
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch7.ipynb
@@ -0,0 +1,172 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 7 The second law"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:7.2 Pg:192"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Entropy in ab part = 0.1213 Btu/lbm R\n",
+      "\n",
+      " Entropy in ac part = 0.1688 Btu/lbm R\n",
+      "\n",
+      " Efficiency = 9.80 percent\n",
+      "The answers are a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "cv=0.175 #Btu/lbm R\n",
+    "R0=1.986\n",
+    "M=29\n",
+    "T2=1040 #R\n",
+    "T1=520 #R\n",
+    "#calculations\n",
+    "cp=cv+R0/M\n",
+    "sab=cv*log(T2/T1)\n",
+    "sac=cp*log(T2/T1)\n",
+    "dqab=cv*(T2-T1)\n",
+    "dqca=cp*(T1-T2)\n",
+    "dqrev=T2*(sac-sab)\n",
+    "eta=(dqab+dqrev+dqca)/(dqab+dqrev)\n",
+    "#results\n",
+    "print \"Entropy in ab part = %.4f Btu/lbm R\"%(sab)\n",
+    "print \"\\n Entropy in ac part = %.4f Btu/lbm R\"%(sac)\n",
+    "print \"\\n Efficiency = %.2f percent\"%(eta*100)\n",
+    "print \"The answers are a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:7.3 Pg:193"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in entropy of the process = 0.0192 Btu/R\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from math import log\n",
+    "#Initialization of variables\n",
+    "tc=32 #F\n",
+    "th=80 #F\n",
+    "mw=5 #lbm\n",
+    "mi=1 #lbm\n",
+    "P=14.7 #psia\n",
+    "cp=1\n",
+    "#calculations\n",
+    "t= (-144*mi+tc*mi+th*mw)/(mw+mi)\n",
+    "ds1=144/(tc+460)\n",
+    "ds2=cp*log((460+t)/(460+tc))\n",
+    "dsice=ds1+ds2\n",
+    "dswater=mw*cp*log((t+460)/(460+th))\n",
+    "ds=dsice+dswater\n",
+    "#results\n",
+    "print \"Change in entropy of the process = %.4f Btu/R\"%(ds)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:7.4 Pg:194"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in available energy = -3.5 Btu/lbm\n",
+      "\n",
+      " The available energy of the isolated system decreased in the amount of  -36.5 Btu/lbm\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "from math import log\n",
+    "\n",
+    "#Initialization of variables\n",
+    "cp=1\n",
+    "T2=60 #F\n",
+    "T1=100 #F\n",
+    "ta=32 #F\n",
+    "#calculations\n",
+    "dq=cp*(T2-T1)\n",
+    "ds=cp*log((460+T2)/(460+T1))\n",
+    "dE=dq-ds*(ta+460)\n",
+    "dec=dq-dE\n",
+    "#results\n",
+    "print \"Change in available energy = %.1f Btu/lbm\"%(dE)\n",
+    "print \"\\n The available energy of the isolated system decreased in the amount of  %.1f Btu/lbm\"%(dec)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/ch9.ipynb b/Thermodynamics_by_Gaggioli_and_Obert/ch9.ipynb
new file mode 100644
index 00000000..6a516fc0
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/ch9.ipynb
@@ -0,0 +1,440 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 9 Properties of the pure substance"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.1 Pg:304"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "Internal energy = -0.0002625 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "T=32 #F\n",
+    "m=1 #lbm\n",
+    "J=778.16\n",
+    "#calculations\n",
+    "print \"From steam tables,\"\n",
+    "hf=0 \n",
+    "p=0.08854 #psia\n",
+    "vf=0.01602 #ft**3/lbm\n",
+    "u=hf-p*144*vf/J\n",
+    "#results\n",
+    "print \"Internal energy = %.7f Btu/lbm\"%(u)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.2 Pg:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from steam tables,\n",
+      "Change in entropy = 0.351 Btu/lbm R\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P=40 #psia\n",
+    "#calculations\n",
+    "print \"from steam tables,\"\n",
+    "hf=200.8 #Btu/lbm\n",
+    "hg=27 #Btu/lbm\n",
+    "T=495  #R\n",
+    "ds=(hf-hg)/T\n",
+    "#results\n",
+    "print \"Change in entropy = %.3f Btu/lbm R\"%(ds)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.3 Pg:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-14,\n",
+      "specific enthalpy = 36.0 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "x=0.35\n",
+    "T=18 #F\n",
+    "#calculations\n",
+    "print \"From table B-14,\"\n",
+    "hf=12.12 #Btu/lbm\n",
+    "hg=80.27 #Btu.lbm\n",
+    "hfg=-hf+hg\n",
+    "h=hf+x*hfg\n",
+    "#results\n",
+    "print \"specific enthalpy = %.1f Btu/lbm\"%(h)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.4 Pg:306"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table B-14,\n",
+      "Heat required = 49.71 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "x=0.35\n",
+    "T=18 #F\n",
+    "T2=55.5 #F\n",
+    "#calculations\n",
+    "print \"From table B-14,\"\n",
+    "hf=12.12 #Btu/lbm\n",
+    "hg=80.27 #Btu.lbm\n",
+    "hfg=-hf+hg\n",
+    "h=hf+x*hfg\n",
+    "h2=85.68 #Btu/lbm\n",
+    "dh=h2-h\n",
+    "#results\n",
+    "print \"Heat required = %.2f Btu/lbm\"%(dh)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.5 Pg:307"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From mollier chart,\n",
+      "enthalpy = 120 Btu/lbm\n",
+      "\n",
+      " Qulaity = 0.83\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P=1460 #psia\n",
+    "T=135 #F\n",
+    "P2=700 #psia\n",
+    "#calculations\n",
+    "print \"From mollier chart,\"\n",
+    "h=120 #Btu/lbm\n",
+    "x=0.83\n",
+    "#results\n",
+    "print \"enthalpy = %d Btu/lbm\"%(h)\n",
+    "print \"\\n Qulaity = %.2f\"%(x)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.6 Pg:307"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table 3,\n",
+      "Heat transferred = 11.4 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "m=1 #lbm\n",
+    "P1=144 #psia\n",
+    "P2=150 #psia\n",
+    "T1=360 #F\n",
+    "J=778.16\n",
+    "#calculations\n",
+    "print \"From table 3,\"\n",
+    "v1=3.160 #ft**3/lbm\n",
+    "h1=1196.5 #Btu/lbm\n",
+    "u1=h1-P1*144*v1/J\n",
+    "h2=1211.4 #Btu/lbm\n",
+    "u2=h2-P2*144*v1/J\n",
+    "dq=u2-u1\n",
+    "#results\n",
+    "print \"Heat transferred = %.1f Btu/lbm\"%(dq)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.7 Pg:307"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From table 3,\n",
+      "Work done = -3.0 Btu/lbm\n",
+      "\n",
+      " In case 2, work required = -5.0 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "T1=100 #F\n",
+    "P2=1000 #psia\n",
+    "x=0.6\n",
+    "J=778.16\n",
+    "#calculations\n",
+    "print \"From table 3,\"\n",
+    "v=0.01613 #ft**3/lbm\n",
+    "P1=0.9 #psia\n",
+    "wrev=-v*(P2-P1)*144/J\n",
+    "dv=0.000051 #ft**3/lbm\n",
+    "wcomp=(P2+P1)/2 *dv*144/J\n",
+    "wact=wrev/x\n",
+    "#results\n",
+    "print \"Work done = %.1f Btu/lbm\"%(wrev)\n",
+    "print \"\\n In case 2, work required = %.1f Btu/lbm\"%(wact)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.8 Pg:308"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "from steam table 2,\n",
+      "Heat transferred = 1120.8 Btu/lbm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "pa=1000 #atm\n",
+    "ta=100 #F\n",
+    "#calculations\n",
+    "hf=67.97 #Btu/lbm\n",
+    "w=3 #Btu/lbm\n",
+    "ha=hf+w\n",
+    "print \"from steam table 2,\"\n",
+    "hc=1191.8 #Btu/lbm\n",
+    "qrev=hc-ha\n",
+    "#results\n",
+    "print \"Heat transferred = %.1f Btu/lbm\"%(qrev)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.9 Pg:309"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "Work done = 266 Btu/lbm\n",
+      "\n",
+      " work done in case 2 = 186.8 Btu/lbm\n",
+      "\n",
+      " Final state pressure = 3 psia\n",
+      "The answer is a bit different due to rounding off error in textbook\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "P1=144 #psia\n",
+    "T1=400 #F\n",
+    "y=0.7\n",
+    "#calculations\n",
+    "print \"From steam tables,\"\n",
+    "h1=1220.4 #Btu/lbm\n",
+    "s1=1.6050 #Btu/lbm R\n",
+    "s2=1.6050 #Btu/lbm R\n",
+    "P2=3 #psia\n",
+    "sf=0.2008 #Btu/lbm R\n",
+    "sfg=1.6855 #Btu/lbm R\n",
+    "x=(s1-sf)/sfg\n",
+    "hf=109.37 #Btu/lbm\n",
+    "hfg=1013.2 #Btu/#bm\n",
+    "h2=hf+x*hfg\n",
+    "work=h1-h2\n",
+    "dw=y*work\n",
+    "h2d=h1-dw\n",
+    "#results\n",
+    "print \"Work done = %d Btu/lbm\"%(work)\n",
+    "print \"\\n work done in case 2 = %.1f Btu/lbm\"%(dw)\n",
+    "print \"\\n Final state pressure = %d psia\"%(P2)\n",
+    "print \"The answer is a bit different due to rounding off error in textbook\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Ex:9.10 Pg:309"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "From steam tables,\n",
+      "Quality of wet steam = 99.8 percent\n"
+     ]
+    }
+   ],
+   "source": [
+    "#Initialization of variables\n",
+    "pb=14.696 #psia\n",
+    "pa=150 #psia\n",
+    "tb=300 #F\n",
+    "#calculations\n",
+    "print \"From steam tables,\"\n",
+    "hb=1192.8 #Btu/lbm\n",
+    "ha=hb\n",
+    "hf=330.51 #Btu/lbm\n",
+    "hfg=863.6 #Btu/lbm\n",
+    "x=(ha-hf)/hfg\n",
+    "#results\n",
+    "print \"Quality of wet steam = %.1f percent\"%(x*100)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/screenshots/changeInMoisture14.png b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/changeInMoisture14.png
new file mode 100644
index 00000000..bc4da4d9
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/changeInMoisture14.png
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/screenshots/degreeOfSaturation14.png b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/degreeOfSaturation14.png
new file mode 100644
index 00000000..7bb12dd0
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/degreeOfSaturation14.png
diff --git a/Thermodynamics_by_Gaggioli_and_Obert/screenshots/humidityratio14.png b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/humidityratio14.png
new file mode 100644
index 00000000..cb399933
--- /dev/null
+++ b/Thermodynamics_by_Gaggioli_and_Obert/screenshots/humidityratio14.png