Added(A)/Deleted(D) following books

 A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10_nEakS5a.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11_MJJTMHn.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15_EjUPJ0v.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18_4VC9Tgt.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1_Cx8gAkH.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21_CbiJJQV.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22_A90BBe5.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23_epZvlzC.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24_ZrVZ9ht.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25_1DX8OSW.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29_BRfETw7.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2_3QlBwiq.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30_SCStTvJ.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6.ipynb
A  Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6_r7ylWQR.ipynb
A  "sample_notebooks/sai kiranmalepati/Sample_Notebook.ipynb"

29 files changed, 4367 insertions, 0 deletions

diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1.ipynb
new file mode 100644
index 00000000..81311d47
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1.ipynb
@@ -0,0 +1,304 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 1:Fundmentals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.1,PAGE NUMBER:3"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_0=-5+273;# K\n",
+    "T_1=35+273;# K\n",
+    "\n",
+    "# Calculation\n",
+    "COP=(T_0)/(T_1-T_0);# Coefficient of performance\n",
+    "print \"Carnot COP=\",round(COP,2),\"(error)\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.2,PAGE NUMBER:4"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_f=80;# Final Temperature in °C\n",
+    "T_i=0;# Initial Temperature in °C\n",
+    "h_f=334.91;# The specific enthalpy of water in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "C=h_f/(T_f-T_i);# The average specific heat capacity in kJ/(kg K)\n",
+    "print \"The average specific heat capacity is\",round(C,3),\"kJ/(kg K)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.3,PAGE NUMBER:4"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "P=1.013;# Pressure in bar\n",
+    "h_fg=2257;# The latent heat of boiling water in kJ/kg\n",
+    "T_b=100; # The boiling point temperature of water in °C\n",
+    "m=1; # The mass of water in kg\n",
+    "T_i=30; # The initial temperature of water in °C\n",
+    "C_p=4.19;# The specific heat of water in kJ/kg°C\n",
+    "\n",
+    "# Calculation\n",
+    "Q=m*((C_p*(T_b-T_i))+h_fg);# The quantity of heat added in kJ\n",
+    "print\"The quantity of heat added is\",round(Q,1),\"kJ\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.4,PAGE NUMBER:6"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "V_1byV_2=2;# Volumetric ratio (given)\n",
+    "p_1=1.01325;# The atmospheric pressure in bar(101325 kPa)\n",
+    "\n",
+    "# Calculation\n",
+    "p_2=V_1byV_2*p_1;# The new pressure in bar\n",
+    "print\"The new pressure,p_2=\",round(p_2,4),\"bar(abs.)\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.5,PAGE NUMBER:7"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "V_1=0.75;# The initial volume in m**3\n",
+    "T_1=273+20; # The initial temperature of water in K\n",
+    "T_2=273+90; # The final temperature of water in K\n",
+    "\n",
+    "# Calculation\n",
+    "V_2=V_1*(T_2/T_1);# The final volume in m**3\n",
+    "print\"The final volume,V_2=\",round(V_2,2),\"m**3\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.6,PAGE NUMBER:7"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "R=287;# The specific gas constant in J/(kg K)\n",
+    "m=5; # The mass of ideal gas in kg\n",
+    "p=101.325;# The atmospheric pressure in kPa\n",
+    "T=273+25;# The temperature of an ideal gas in K\n",
+    "\n",
+    "# Calculation\n",
+    "V=(m*R*T)/(p*1000);# The volume of an ideal gas in m**3\n",
+    "print\"The volume of an ideal gas is\",round(V,2),\"m**3\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.7,PAGE NUMBER:7,8"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "m_N=0.906;# The mass of nitrogen in a cubic metre of air in kg\n",
+    "R_N=297;# The specific gas constant of nitrogen in J/kg K\n",
+    "m_O=0.278;# The mass of oxygen in a cubic metre of air in kg\n",
+    "R_O=260;# The specific gas constant of oxygen in J/kg K\n",
+    "m_A=0.015;# The mass of argon in a cubic metre of air in kg\n",
+    "R_A=208;# The specific gas constant of argon in J/kg K\n",
+    "T=273.15+20;# The temperature of air in K\n",
+    "\n",
+    "# Calculation\n",
+    "p_N=m_N*R_N*T;# The pressure of nitrogen in Pa\n",
+    "p_O=m_O*R_O*T;# The pressure of oxygen in Pa\n",
+    "p_A=m_A*R_A*T;# The pressure of argon in Pa\n",
+    "p_t=p_N+p_O+p_A;# The total pressure in Pa\n",
+    "print\"The total pressure is\",round(p_t,0),\"Pa\",\"(\",round(p_t/10**5,5),\"bar)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.8,PAGE NUMBER:8"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declartion\n",
+    "t=225;# The wall thickness in mm\n",
+    "k=0.60;# Thermal conductivity in W/(m K)\n",
+    "L=10;# Length in m\n",
+    "h=3;# Height in m\n",
+    "delT=25;# The temperature difference between the inside and outside faces in K\n",
+    "\n",
+    "# Calculation\n",
+    "Q_t=(L*h*k*delT*1000)/(t);# The rate of heat conduction in W\n",
+    "print\"The rate of heat conduction,Q_t=\",round(Q_t,0),\"W\"\"(or)\",round(Q_t/1000,0),\"kW)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.9,PAGE NUMBER:10"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declartion\n",
+    "R_i=0.3;# The inside surface resistance in (m**2 K)/W\n",
+    "R_c=1/2.8;# The thermal conductance of plastered surface in (m**2 K)/W\n",
+    "R_o=0.05;# The outside surface resistance in (m**2 K)/W\n",
+    "\n",
+    "# Calculation\n",
+    "R_t=R_i+R_c+R_o;# The total thermal resistance in (m**2 K)/W\n",
+    "U=1/R_t;# The overall transmittance in W/(m**2 K)\n",
+    "print\"The overall transmittance,U=\",round(U,3),\" W/(m**2 K)\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.10,PAGE NUMBER:12"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declartion\n",
+    "T_f=3;# The temperature of fluid in °C\n",
+    "T_wi=11.5;# The temperature of water at inlet in °C\n",
+    "T_wo=6.4;# The temperature of water at outlet in °C\n",
+    "A=420;# The surface area in m**2\n",
+    "U=110;# The thermal transmittance in W/(m**2 K) \n",
+    "\n",
+    "# Calculation\n",
+    "delT_max=T_wi-T_f;# The maximum temperature difference in K\n",
+    "delT_min=T_wo-T_f;# The minimum temperature difference in K\n",
+    "LMTD=(delT_max-delT_min)/math.log(delT_max/delT_min);\n",
+    "Q_f=U*A*LMTD;# The amount of heat transfer in W\n",
+    "print\"The logarithmic mean temperature difference is\",round(LMTD,3),\"K\"\n",
+    "print\"The amount of heat transfer is\",round(Q_f,0),\"W (round off error)\",\"or\",round(Q_f/1000,0),\"kW\""
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10.ipynb
new file mode 100644
index 00000000..2855a29c
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10.ipynb
@@ -0,0 +1,193 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 10:Component Selection and Balancing"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.1,PAGE NUMBER:136"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "w_a=8.4;# The mass flow rate of air in kg/s\n",
+    "R=3.8;# Rating of an air-cooling evaporator in kW/k\n",
+    "T_a=-15;# Entering air temperature in °C\n",
+    "T_r=-21;# Refrigerant temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=(T_a+273)-(T_r+273);# Rating LMTD in K\n",
+    "E=R*deltaT;# Rated duty in kW\n",
+    "C_pair=1.006;# kJ/kg.K\n",
+    "T_ar=E/(C_pair*w_a);# Reduction in air temperature in °C \n",
+    "T_al=T_a-T_ar;# Air leaving temperature in °C\n",
+    "deltaT_min=(T_al+273)-(T_r+273);# K\n",
+    "deltaT_max=deltaT;# K\n",
+    "LMTD=(deltaT_max-deltaT_min)/(math.log(deltaT_max/deltaT_min));\n",
+    "print\"\\nLMTD=%1.1f K\"%LMTD"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Example 10.2,PAGE NUMBER:136"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q=45;# The sensible heat extracted by an air-cooling coil in kW\n",
+    "T_in=24;# The entering air temperature in °C\n",
+    "T_out=18;# The leaving air temperature in °C\n",
+    "T_e=11;#  Refrigerant  evaporating temperature in °C\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "Af=[100,95,90,85];# Air flow (%)\n",
+    "m=[7.35,6.99,6.62,6.25];# Mass air flow (kg/s)\n",
+    "T_a=[24,24,24,24];# Air temperature on coil (°C)\n",
+    "deltaT=[6,6.3,6.7,7.1];# ΔT for 45 kW (K)\n",
+    "T_aoff=[18,17.7,17.3,16.9];# Air temperature off coil (°C)\n",
+    "LMTD=[9.7,9.5,9.2,9.0];# LMTD,refrigerant at 11°C (K)\n",
+    "h=[1,0.96,0.92,0.88];# h, in terms of design (from V0.8) \n",
+    "\n",
+    "# Calculation\n",
+    "m_af=Q/(C_pa*(T_in-T_out));\n",
+    "Capacity=[(45*h[0]*LMTD[0])/9.7,(45*h[1]*LMTD[1])/9.7,(45*h[2]*LMTD[2])/9.7,(45*h[3]*LMTD[3])/9.7];# kW\n",
+    "print\"\\nDesign mass air flow=%1.2f kg/s\"%m_af\n",
+    "print\"The cooling capacity at 100,95,90and 85 percentage mass air flow=%2.0f,%2.1f,%2.1fand %2.1f kW\"%(Capacity[0],Capacity[1],Capacity[2],Capacity[3])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.3,PAGE NUMBER:140"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "P_c=10;# kW\n",
+    "T_e=-35;# Evaporating temperature in °C\n",
+    "T_c=40;# Condensing temperature in °C\n",
+    "T_s=5;# Subcooling temperature in K\n",
+    "T_cin=20;# Compressor inlet temperature in °C\n",
+    "T_cout=0;# Zero subcooling temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "#(a)\n",
+    "v_s1=146.46;# m**3/kg\n",
+    "v_s2=135.25;# m**3/kg\n",
+    "v_sr=v_s1/v_s2;# The ratio of specific volume\n",
+    "# Assuming the compressor pumps the same volume flowrate:\n",
+    "m_1bym_2=v_sr;# Flow rate ratio\n",
+    "print\"\\nFlow rate ratio,m_2/m_1=%1.3f\"%m_1bym_2\n",
+    "#(b)\n",
+    "h_1=392.51;# Suction gas enthalpy at 20°C in kJ/kg\n",
+    "h_2=375.19;# Suction gas enthalpy at 0°C in kJ/kg\n",
+    "h_f=257.77;# Liquid enthalpy at the expansion valve inlet at 40°C in kJ/kg\n",
+    "dh_1=h_1-h_f;# Evaporator enthalpy difference at rating condition in kJ/kg\n",
+    "dh_2=h_2-h_f;# Evaporator enthalpy difference with 0°C suction in kJ/kg\n",
+    "dh_r=dh_2/dh_1;# Enthalpy difference ratio\n",
+    "C_c=P_c*m_1bym_2*dh_r;# Compressor capacity corrected for suction temperature change in kW\n",
+    "print\"\\nCompressor capacity corrected for suction temperature change=%1.2f kW\"%C_c\n",
+    "#(c)\n",
+    "h_f=249.67;# Liquid enthalpy at the expansion valve inlet at 35°C in kJ/kg\n",
+    "dh=h_2-h_f;# Evaporator enthalpy difference at application condition in kJ/kg\n",
+    "dh_r=dh/dh_1;# Enthalpy difference ratio\n",
+    "C_cact=P_c*m_1bym_2*dh_r;# Actual compressor capacity in kW\n",
+    "print\"\\nActual compressor capacity=%2.2f kW\"%C_cact\n",
+    "#(d)\n",
+    "h_g=350.13;# Suction gas enthalpy at evaporator outlet, -30°C (5 K superheat) in kJ/kg\n",
+    "dh_e=h_g-h_f;# Useful evaporator enthalpy difference in kJ/kg\n",
+    "dh_r=dh_e/dh_1;# Enthalpy difference ratio\n",
+    "C_eact=P_c*m_1bym_2*dh_r;# Actual evaporator capacity in kW\n",
+    "print\"\\nActual evaporator capacity=%1.2f kW\"%C_eact"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.4,PAGE NUMBER:142"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_c1=30;# Condensing temperature for larger condenser in °C\n",
+    "T_c2=35;# Condensing temperature for smaller condenser in °C\n",
+    "Rc_1=242;# Rated capacity of plant for larger condenser in kW\n",
+    "Rc_2=218;# Rated capacity of plant for smaller condenser in kW\n",
+    "Rt_1=1802;# Running time (kW-h)\n",
+    "Rt_2=2000;# Running time (kW-h)\n",
+    "Ci_1=60;# Compressor electrical input power in kW\n",
+    "Ci_2=70;# Compressor electrical input power in kW\n",
+    "Ec_1=11533;# Electricity cost per year (£)\n",
+    "Ec_2=14933;# Electricity cost per year (£)\n",
+    "C_1=14000;# Cost of the larger condenser in £\n",
+    "C_2=8500;# Cost of the smaller condenser in £\n",
+    "\n",
+    "# Calculation\n",
+    "Es=Ec_2-Ec_1;# Cost of the larger condenser in £\n",
+    "Bet=(C_1-C_2)*Es**-1;# Break-even time in years\n",
+    "print\"Break-even time=%1.1f years\"%Bet"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10_nEakS5a.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10_nEakS5a.ipynb
new file mode 100644
index 00000000..2855a29c
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER10_nEakS5a.ipynb
@@ -0,0 +1,193 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 10:Component Selection and Balancing"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.1,PAGE NUMBER:136"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "w_a=8.4;# The mass flow rate of air in kg/s\n",
+    "R=3.8;# Rating of an air-cooling evaporator in kW/k\n",
+    "T_a=-15;# Entering air temperature in °C\n",
+    "T_r=-21;# Refrigerant temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=(T_a+273)-(T_r+273);# Rating LMTD in K\n",
+    "E=R*deltaT;# Rated duty in kW\n",
+    "C_pair=1.006;# kJ/kg.K\n",
+    "T_ar=E/(C_pair*w_a);# Reduction in air temperature in °C \n",
+    "T_al=T_a-T_ar;# Air leaving temperature in °C\n",
+    "deltaT_min=(T_al+273)-(T_r+273);# K\n",
+    "deltaT_max=deltaT;# K\n",
+    "LMTD=(deltaT_max-deltaT_min)/(math.log(deltaT_max/deltaT_min));\n",
+    "print\"\\nLMTD=%1.1f K\"%LMTD"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Example 10.2,PAGE NUMBER:136"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q=45;# The sensible heat extracted by an air-cooling coil in kW\n",
+    "T_in=24;# The entering air temperature in °C\n",
+    "T_out=18;# The leaving air temperature in °C\n",
+    "T_e=11;#  Refrigerant  evaporating temperature in °C\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "Af=[100,95,90,85];# Air flow (%)\n",
+    "m=[7.35,6.99,6.62,6.25];# Mass air flow (kg/s)\n",
+    "T_a=[24,24,24,24];# Air temperature on coil (°C)\n",
+    "deltaT=[6,6.3,6.7,7.1];# ΔT for 45 kW (K)\n",
+    "T_aoff=[18,17.7,17.3,16.9];# Air temperature off coil (°C)\n",
+    "LMTD=[9.7,9.5,9.2,9.0];# LMTD,refrigerant at 11°C (K)\n",
+    "h=[1,0.96,0.92,0.88];# h, in terms of design (from V0.8) \n",
+    "\n",
+    "# Calculation\n",
+    "m_af=Q/(C_pa*(T_in-T_out));\n",
+    "Capacity=[(45*h[0]*LMTD[0])/9.7,(45*h[1]*LMTD[1])/9.7,(45*h[2]*LMTD[2])/9.7,(45*h[3]*LMTD[3])/9.7];# kW\n",
+    "print\"\\nDesign mass air flow=%1.2f kg/s\"%m_af\n",
+    "print\"The cooling capacity at 100,95,90and 85 percentage mass air flow=%2.0f,%2.1f,%2.1fand %2.1f kW\"%(Capacity[0],Capacity[1],Capacity[2],Capacity[3])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.3,PAGE NUMBER:140"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "P_c=10;# kW\n",
+    "T_e=-35;# Evaporating temperature in °C\n",
+    "T_c=40;# Condensing temperature in °C\n",
+    "T_s=5;# Subcooling temperature in K\n",
+    "T_cin=20;# Compressor inlet temperature in °C\n",
+    "T_cout=0;# Zero subcooling temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "#(a)\n",
+    "v_s1=146.46;# m**3/kg\n",
+    "v_s2=135.25;# m**3/kg\n",
+    "v_sr=v_s1/v_s2;# The ratio of specific volume\n",
+    "# Assuming the compressor pumps the same volume flowrate:\n",
+    "m_1bym_2=v_sr;# Flow rate ratio\n",
+    "print\"\\nFlow rate ratio,m_2/m_1=%1.3f\"%m_1bym_2\n",
+    "#(b)\n",
+    "h_1=392.51;# Suction gas enthalpy at 20°C in kJ/kg\n",
+    "h_2=375.19;# Suction gas enthalpy at 0°C in kJ/kg\n",
+    "h_f=257.77;# Liquid enthalpy at the expansion valve inlet at 40°C in kJ/kg\n",
+    "dh_1=h_1-h_f;# Evaporator enthalpy difference at rating condition in kJ/kg\n",
+    "dh_2=h_2-h_f;# Evaporator enthalpy difference with 0°C suction in kJ/kg\n",
+    "dh_r=dh_2/dh_1;# Enthalpy difference ratio\n",
+    "C_c=P_c*m_1bym_2*dh_r;# Compressor capacity corrected for suction temperature change in kW\n",
+    "print\"\\nCompressor capacity corrected for suction temperature change=%1.2f kW\"%C_c\n",
+    "#(c)\n",
+    "h_f=249.67;# Liquid enthalpy at the expansion valve inlet at 35°C in kJ/kg\n",
+    "dh=h_2-h_f;# Evaporator enthalpy difference at application condition in kJ/kg\n",
+    "dh_r=dh/dh_1;# Enthalpy difference ratio\n",
+    "C_cact=P_c*m_1bym_2*dh_r;# Actual compressor capacity in kW\n",
+    "print\"\\nActual compressor capacity=%2.2f kW\"%C_cact\n",
+    "#(d)\n",
+    "h_g=350.13;# Suction gas enthalpy at evaporator outlet, -30°C (5 K superheat) in kJ/kg\n",
+    "dh_e=h_g-h_f;# Useful evaporator enthalpy difference in kJ/kg\n",
+    "dh_r=dh_e/dh_1;# Enthalpy difference ratio\n",
+    "C_eact=P_c*m_1bym_2*dh_r;# Actual evaporator capacity in kW\n",
+    "print\"\\nActual evaporator capacity=%1.2f kW\"%C_eact"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10.4,PAGE NUMBER:142"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_c1=30;# Condensing temperature for larger condenser in °C\n",
+    "T_c2=35;# Condensing temperature for smaller condenser in °C\n",
+    "Rc_1=242;# Rated capacity of plant for larger condenser in kW\n",
+    "Rc_2=218;# Rated capacity of plant for smaller condenser in kW\n",
+    "Rt_1=1802;# Running time (kW-h)\n",
+    "Rt_2=2000;# Running time (kW-h)\n",
+    "Ci_1=60;# Compressor electrical input power in kW\n",
+    "Ci_2=70;# Compressor electrical input power in kW\n",
+    "Ec_1=11533;# Electricity cost per year (£)\n",
+    "Ec_2=14933;# Electricity cost per year (£)\n",
+    "C_1=14000;# Cost of the larger condenser in £\n",
+    "C_2=8500;# Cost of the smaller condenser in £\n",
+    "\n",
+    "# Calculation\n",
+    "Es=Ec_2-Ec_1;# Cost of the larger condenser in £\n",
+    "Bet=(C_1-C_2)*Es**-1;# Break-even time in years\n",
+    "print\"Break-even time=%1.1f years\"%Bet"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11.ipynb
new file mode 100644
index 00000000..2c6f3f29
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11.ipynb
@@ -0,0 +1,88 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 11:Installation and Construction"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 11.1,PAGE NUMBER:152"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_c=34;# The condensing temperature in °C\n",
+    "T_s=30;# The subcooled temperature in °C\n",
+    "g=9.81;# m/s**2\n",
+    "\n",
+    "# Calculation\n",
+    "P_c=15.69;# Saturation pressure at 34°C in bar\n",
+    "P_s=14.18;# Saturation pressure at 30°C in bar\n",
+    "dp=P_c-P_s;# Permissible pressure drop in bar\n",
+    "rho=1022;# Specific mass of liquid in kg/m**3;\n",
+    "H=(dp*10**5)/(rho*g);# Possible loss in static head in m\n",
+    "print\"Possible loss in static head=%2.1f m\"%H"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 11.2,PAGE NUMBER:158"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_a=20;# The ambient temperature in °C\n",
+    "m_p=10;# g\n",
+    "\n",
+    "# Calculation\n",
+    "P_v=10.34;# Vapour pressure of R407C at 20°C in bar abs\n",
+    "P_o=11.70;# Observed pressure in bar abs\n",
+    "P_p=P_o-P_v;# Partial pressure of non-condensible gas in bar abs\n",
+    "M_m=(0.23*52)+(0.25*120)+(0.52*102);# Molecular mass\n",
+    "print\"\\nPartial pressure of non-condensible gas=%1.2f bar abs \\nMolecular mass=%2.0f\"%(P_p,M_m)"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11_MJJTMHn.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11_MJJTMHn.ipynb
new file mode 100644
index 00000000..2c6f3f29
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER11_MJJTMHn.ipynb
@@ -0,0 +1,88 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 11:Installation and Construction"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 11.1,PAGE NUMBER:152"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_c=34;# The condensing temperature in °C\n",
+    "T_s=30;# The subcooled temperature in °C\n",
+    "g=9.81;# m/s**2\n",
+    "\n",
+    "# Calculation\n",
+    "P_c=15.69;# Saturation pressure at 34°C in bar\n",
+    "P_s=14.18;# Saturation pressure at 30°C in bar\n",
+    "dp=P_c-P_s;# Permissible pressure drop in bar\n",
+    "rho=1022;# Specific mass of liquid in kg/m**3;\n",
+    "H=(dp*10**5)/(rho*g);# Possible loss in static head in m\n",
+    "print\"Possible loss in static head=%2.1f m\"%H"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 11.2,PAGE NUMBER:158"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_a=20;# The ambient temperature in °C\n",
+    "m_p=10;# g\n",
+    "\n",
+    "# Calculation\n",
+    "P_v=10.34;# Vapour pressure of R407C at 20°C in bar abs\n",
+    "P_o=11.70;# Observed pressure in bar abs\n",
+    "P_p=P_o-P_v;# Partial pressure of non-condensible gas in bar abs\n",
+    "M_m=(0.23*52)+(0.25*120)+(0.52*102);# Molecular mass\n",
+    "print\"\\nPartial pressure of non-condensible gas=%1.2f bar abs \\nMolecular mass=%2.0f\"%(P_p,M_m)"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15.ipynb
new file mode 100644
index 00000000..f941b77f
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15.ipynb
@@ -0,0 +1,100 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 15:Cold storage"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 15.1,PAGE NUMBER:188"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "n=2;# The number of two pellet truck doors\n",
+    "m_n=300;#The number of traffic movements per day\n",
+    "t=30;# seconds\n",
+    "\n",
+    "# Calculation\n",
+    "T=n*m_n*t;# The time for the door openings seconds per day \n",
+    "A=2.2*3.2;# The cross sectional area in m**2\n",
+    "v=1;# m/s\n",
+    "I=A*T*v;# The air infiltration in m**3/d\n",
+    "V=50*70*10;# The store volume in m**3\n",
+    "R=I/V;# The rate of air change per day\n",
+    "print\"\\nThe store volume is %5.0f m**3. \\nThe rate of air change is %1.1f per day.\"%(V,R)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 15.2,PAGE NUMBER:188"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T=5;#  The dry bulb temperature in \n",
+    "R=3.6;# The rate of air change per day\n",
+    "V=35000;# The store volume in m**3\n",
+    "v_spa=0.8;# The specific volume in m**3/kg\n",
+    "q=600;# m**3/h\n",
+    "n=2;# The number of two pellet truck doors\n",
+    "h_1=15.9;# kJ/kg\n",
+    "h_2=-24.3;# kJ/kg\n",
+    "T_1=20;# °C\n",
+    "T_2=-25;# °C\n",
+    "t=24;# Time duration for one day in hours\n",
+    "t_s=24*60*60;# Time duration for one day in seconds\n",
+    "\n",
+    "# Calculation\n",
+    "R_woh=V*R/v_spa;# The rate of air change without dehumidification in kg/day\n",
+    "Q_woh=R_woh*(h_1-h_2)/t_s;# The cooling load without dehumidification in kW\n",
+    "R_wh=q*n*t/v_spa;# The rate of air change with dehumidification in kg/day\n",
+    "Q_wh=R_wh*(T_1-T_2)/t_s;# The cooling load with dehumidification in kW\n",
+    "print\"\\nThe rate of air change without dehumidification is %5.0f kg/day. \\nThe cooling load without dehumidification %2.1f kW(calculation error).\"%(R_woh,Q_woh)\n",
+    "print\"\\nThe rate of air change with dehumidification is %5.0f kg/day. \\nThe cooling load with dehumidification %2.2f kW.\"%(R_wh,Q_wh)\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15_EjUPJ0v.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15_EjUPJ0v.ipynb
new file mode 100644
index 00000000..f941b77f
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER15_EjUPJ0v.ipynb
@@ -0,0 +1,100 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 15:Cold storage"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 15.1,PAGE NUMBER:188"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "n=2;# The number of two pellet truck doors\n",
+    "m_n=300;#The number of traffic movements per day\n",
+    "t=30;# seconds\n",
+    "\n",
+    "# Calculation\n",
+    "T=n*m_n*t;# The time for the door openings seconds per day \n",
+    "A=2.2*3.2;# The cross sectional area in m**2\n",
+    "v=1;# m/s\n",
+    "I=A*T*v;# The air infiltration in m**3/d\n",
+    "V=50*70*10;# The store volume in m**3\n",
+    "R=I/V;# The rate of air change per day\n",
+    "print\"\\nThe store volume is %5.0f m**3. \\nThe rate of air change is %1.1f per day.\"%(V,R)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 15.2,PAGE NUMBER:188"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T=5;#  The dry bulb temperature in \n",
+    "R=3.6;# The rate of air change per day\n",
+    "V=35000;# The store volume in m**3\n",
+    "v_spa=0.8;# The specific volume in m**3/kg\n",
+    "q=600;# m**3/h\n",
+    "n=2;# The number of two pellet truck doors\n",
+    "h_1=15.9;# kJ/kg\n",
+    "h_2=-24.3;# kJ/kg\n",
+    "T_1=20;# °C\n",
+    "T_2=-25;# °C\n",
+    "t=24;# Time duration for one day in hours\n",
+    "t_s=24*60*60;# Time duration for one day in seconds\n",
+    "\n",
+    "# Calculation\n",
+    "R_woh=V*R/v_spa;# The rate of air change without dehumidification in kg/day\n",
+    "Q_woh=R_woh*(h_1-h_2)/t_s;# The cooling load without dehumidification in kW\n",
+    "R_wh=q*n*t/v_spa;# The rate of air change with dehumidification in kg/day\n",
+    "Q_wh=R_wh*(T_1-T_2)/t_s;# The cooling load with dehumidification in kW\n",
+    "print\"\\nThe rate of air change without dehumidification is %5.0f kg/day. \\nThe cooling load without dehumidification %2.1f kW(calculation error).\"%(R_woh,Q_woh)\n",
+    "print\"\\nThe rate of air change with dehumidification is %5.0f kg/day. \\nThe cooling load with dehumidification %2.2f kW.\"%(R_wh,Q_wh)\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18.ipynb
new file mode 100644
index 00000000..e1962b2c
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18.ipynb
@@ -0,0 +1,162 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 18:Refrigeration Load Estimation"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.1,PAGE NUMBER:228"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_1=15;# °C\n",
+    "T_2=0;# °C\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.k\n",
+    "m=20*10**3;# The mass flow rate of water in kg/day\n",
+    "h_l=334;# kJ/kg\n",
+    "t=24*3600;# The time available for cooling in s\n",
+    "\n",
+    "# Calculation\n",
+    "Q=(m*((C_pw*T_1)+334))/t;# The cooling load in kW\n",
+    "print\"The cooling load,Q=%2.0f kW.\"%Q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.2,PAGE NUMBER:228"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_1=22;# °C\n",
+    "T_2=1;# °C\n",
+    "C_p=3.1;# The specific heat capacity of meat in kJ/kg.K\n",
+    "m=8*10**3;# The mass of meat in kg\n",
+    "t=14*3600;# The time available for cooling in s\n",
+    "\n",
+    "# Calculation\n",
+    "Q=(m*((C_p*(T_1-T_2))))/t;# The cooling load in kW\n",
+    "print\"The cooling load,Q=%2.1f kW.\"%Q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.3,PAGE NUMBER:230"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "n=12;# The number of lighting fittings\n",
+    "P=280;# W\n",
+    "P_3f=660;# W\n",
+    "P_h=18;# kW\n",
+    "I=80;# A\n",
+    "V=24;# V\n",
+    "\n",
+    "# Calculation\n",
+    "L=[1.12,3.36];# Lighting,12*280,8h/day [Average over 24 h,Peak]\n",
+    "F=[7.78,7.92];# Fan motors, 12*660 W [Average over 24 h,Peak]\n",
+    "Dh=[1.50,18.00];# Defrost heaters,72 kW,1/2 h/day [Average over 24 h,Peak]\n",
+    "Fl=[0.21,1.92];# Fork-lift,1.92 kW,(1/3)*8h [Average over 24 h,Peak]\n",
+    "Fld=[0,0.12];# Fork-lift driver,120 kW,(1/3)*8h [Average over 24 h,Peak]\n",
+    "P=[0,0.24];# Packers,240 W,(1/3)*8h [Average over 24 h,Peak]\n",
+    "Avg=L[0]+F[0]+Dh[0]+Fl[0]+Fld[0]+P[0];# Average over 24 h\n",
+    "Peak=L[1]+F[1]+Dh[1]+Fl[1]+Fld[1]+P[1];# Peak\n",
+    "print\"\\nAverage over 24 h=%2.2f \\nPeak=%2.2f\"%(Avg,Peak)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.6,PAGE NUMBER:231"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m=1000;# The capacity of meat store in tonnes\n",
+    "m_l=50;# The amount of meat leaving the store in t/day\n",
+    "m_s=300;# The amount of meat arrives from the ships in t/day\n",
+    "t=24*3600;# Time in s\n",
+    "\n",
+    "# Calculation\n",
+    "# Case(1)\n",
+    "m=90;# t/day\n",
+    "T_1=2;# °C\n",
+    "T_2=-12;# °C\n",
+    "C=3.2;# Specific heat capacity in kJ/(kg.K)\n",
+    "T_fp=-1;# Freezing point of meat in °C\n",
+    "h_fg=225;# Latent heat of freezing in kJ/kg\n",
+    "C_fm=1.63;# Specific heat of frozen meat in kJ/(kg.K)\n",
+    "Q_f=(m*1000*((C*3)+h_fg+(C_fm*11)))/(t);# Cooling load in kW\n",
+    "print\"\\nCase(1):Cooling load,Q_f=%3.0f kW\"%Q_f\n",
+    "# Case(2)\n",
+    "Q_f=(m_s*10**3*(C_fm*T_1))/t;# Cooling load in kW\n",
+    "print\"\\nCase(2):Cooling load,Q_f=%2.0f kW\"%Q_f\n",
+    "# Case(3)\n",
+    "Q_f=(m_l*10**3*((C*3)+h_fg+(C_fm*11)))/t;# Cooling load in kW\n",
+    "print\"\\nCase(3):Cooling load,Q_f=%3.0f kW\"%Q_f"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18_4VC9Tgt.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18_4VC9Tgt.ipynb
new file mode 100644
index 00000000..e1962b2c
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER18_4VC9Tgt.ipynb
@@ -0,0 +1,162 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 18:Refrigeration Load Estimation"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.1,PAGE NUMBER:228"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_1=15;# °C\n",
+    "T_2=0;# °C\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.k\n",
+    "m=20*10**3;# The mass flow rate of water in kg/day\n",
+    "h_l=334;# kJ/kg\n",
+    "t=24*3600;# The time available for cooling in s\n",
+    "\n",
+    "# Calculation\n",
+    "Q=(m*((C_pw*T_1)+334))/t;# The cooling load in kW\n",
+    "print\"The cooling load,Q=%2.0f kW.\"%Q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.2,PAGE NUMBER:228"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_1=22;# °C\n",
+    "T_2=1;# °C\n",
+    "C_p=3.1;# The specific heat capacity of meat in kJ/kg.K\n",
+    "m=8*10**3;# The mass of meat in kg\n",
+    "t=14*3600;# The time available for cooling in s\n",
+    "\n",
+    "# Calculation\n",
+    "Q=(m*((C_p*(T_1-T_2))))/t;# The cooling load in kW\n",
+    "print\"The cooling load,Q=%2.1f kW.\"%Q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.3,PAGE NUMBER:230"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "n=12;# The number of lighting fittings\n",
+    "P=280;# W\n",
+    "P_3f=660;# W\n",
+    "P_h=18;# kW\n",
+    "I=80;# A\n",
+    "V=24;# V\n",
+    "\n",
+    "# Calculation\n",
+    "L=[1.12,3.36];# Lighting,12*280,8h/day [Average over 24 h,Peak]\n",
+    "F=[7.78,7.92];# Fan motors, 12*660 W [Average over 24 h,Peak]\n",
+    "Dh=[1.50,18.00];# Defrost heaters,72 kW,1/2 h/day [Average over 24 h,Peak]\n",
+    "Fl=[0.21,1.92];# Fork-lift,1.92 kW,(1/3)*8h [Average over 24 h,Peak]\n",
+    "Fld=[0,0.12];# Fork-lift driver,120 kW,(1/3)*8h [Average over 24 h,Peak]\n",
+    "P=[0,0.24];# Packers,240 W,(1/3)*8h [Average over 24 h,Peak]\n",
+    "Avg=L[0]+F[0]+Dh[0]+Fl[0]+Fld[0]+P[0];# Average over 24 h\n",
+    "Peak=L[1]+F[1]+Dh[1]+Fl[1]+Fld[1]+P[1];# Peak\n",
+    "print\"\\nAverage over 24 h=%2.2f \\nPeak=%2.2f\"%(Avg,Peak)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 18.6,PAGE NUMBER:231"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m=1000;# The capacity of meat store in tonnes\n",
+    "m_l=50;# The amount of meat leaving the store in t/day\n",
+    "m_s=300;# The amount of meat arrives from the ships in t/day\n",
+    "t=24*3600;# Time in s\n",
+    "\n",
+    "# Calculation\n",
+    "# Case(1)\n",
+    "m=90;# t/day\n",
+    "T_1=2;# °C\n",
+    "T_2=-12;# °C\n",
+    "C=3.2;# Specific heat capacity in kJ/(kg.K)\n",
+    "T_fp=-1;# Freezing point of meat in °C\n",
+    "h_fg=225;# Latent heat of freezing in kJ/kg\n",
+    "C_fm=1.63;# Specific heat of frozen meat in kJ/(kg.K)\n",
+    "Q_f=(m*1000*((C*3)+h_fg+(C_fm*11)))/(t);# Cooling load in kW\n",
+    "print\"\\nCase(1):Cooling load,Q_f=%3.0f kW\"%Q_f\n",
+    "# Case(2)\n",
+    "Q_f=(m_s*10**3*(C_fm*T_1))/t;# Cooling load in kW\n",
+    "print\"\\nCase(2):Cooling load,Q_f=%2.0f kW\"%Q_f\n",
+    "# Case(3)\n",
+    "Q_f=(m_l*10**3*((C*3)+h_fg+(C_fm*11)))/t;# Cooling load in kW\n",
+    "print\"\\nCase(3):Cooling load,Q_f=%3.0f kW\"%Q_f"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1_Cx8gAkH.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1_Cx8gAkH.ipynb
new file mode 100644
index 00000000..81311d47
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER1_Cx8gAkH.ipynb
@@ -0,0 +1,304 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 1:Fundmentals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.1,PAGE NUMBER:3"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_0=-5+273;# K\n",
+    "T_1=35+273;# K\n",
+    "\n",
+    "# Calculation\n",
+    "COP=(T_0)/(T_1-T_0);# Coefficient of performance\n",
+    "print \"Carnot COP=\",round(COP,2),\"(error)\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.2,PAGE NUMBER:4"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_f=80;# Final Temperature in °C\n",
+    "T_i=0;# Initial Temperature in °C\n",
+    "h_f=334.91;# The specific enthalpy of water in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "C=h_f/(T_f-T_i);# The average specific heat capacity in kJ/(kg K)\n",
+    "print \"The average specific heat capacity is\",round(C,3),\"kJ/(kg K)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.3,PAGE NUMBER:4"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "P=1.013;# Pressure in bar\n",
+    "h_fg=2257;# The latent heat of boiling water in kJ/kg\n",
+    "T_b=100; # The boiling point temperature of water in °C\n",
+    "m=1; # The mass of water in kg\n",
+    "T_i=30; # The initial temperature of water in °C\n",
+    "C_p=4.19;# The specific heat of water in kJ/kg°C\n",
+    "\n",
+    "# Calculation\n",
+    "Q=m*((C_p*(T_b-T_i))+h_fg);# The quantity of heat added in kJ\n",
+    "print\"The quantity of heat added is\",round(Q,1),\"kJ\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.4,PAGE NUMBER:6"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "V_1byV_2=2;# Volumetric ratio (given)\n",
+    "p_1=1.01325;# The atmospheric pressure in bar(101325 kPa)\n",
+    "\n",
+    "# Calculation\n",
+    "p_2=V_1byV_2*p_1;# The new pressure in bar\n",
+    "print\"The new pressure,p_2=\",round(p_2,4),\"bar(abs.)\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.5,PAGE NUMBER:7"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "V_1=0.75;# The initial volume in m**3\n",
+    "T_1=273+20; # The initial temperature of water in K\n",
+    "T_2=273+90; # The final temperature of water in K\n",
+    "\n",
+    "# Calculation\n",
+    "V_2=V_1*(T_2/T_1);# The final volume in m**3\n",
+    "print\"The final volume,V_2=\",round(V_2,2),\"m**3\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.6,PAGE NUMBER:7"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "R=287;# The specific gas constant in J/(kg K)\n",
+    "m=5; # The mass of ideal gas in kg\n",
+    "p=101.325;# The atmospheric pressure in kPa\n",
+    "T=273+25;# The temperature of an ideal gas in K\n",
+    "\n",
+    "# Calculation\n",
+    "V=(m*R*T)/(p*1000);# The volume of an ideal gas in m**3\n",
+    "print\"The volume of an ideal gas is\",round(V,2),\"m**3\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.7,PAGE NUMBER:7,8"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "m_N=0.906;# The mass of nitrogen in a cubic metre of air in kg\n",
+    "R_N=297;# The specific gas constant of nitrogen in J/kg K\n",
+    "m_O=0.278;# The mass of oxygen in a cubic metre of air in kg\n",
+    "R_O=260;# The specific gas constant of oxygen in J/kg K\n",
+    "m_A=0.015;# The mass of argon in a cubic metre of air in kg\n",
+    "R_A=208;# The specific gas constant of argon in J/kg K\n",
+    "T=273.15+20;# The temperature of air in K\n",
+    "\n",
+    "# Calculation\n",
+    "p_N=m_N*R_N*T;# The pressure of nitrogen in Pa\n",
+    "p_O=m_O*R_O*T;# The pressure of oxygen in Pa\n",
+    "p_A=m_A*R_A*T;# The pressure of argon in Pa\n",
+    "p_t=p_N+p_O+p_A;# The total pressure in Pa\n",
+    "print\"The total pressure is\",round(p_t,0),\"Pa\",\"(\",round(p_t/10**5,5),\"bar)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.8,PAGE NUMBER:8"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declartion\n",
+    "t=225;# The wall thickness in mm\n",
+    "k=0.60;# Thermal conductivity in W/(m K)\n",
+    "L=10;# Length in m\n",
+    "h=3;# Height in m\n",
+    "delT=25;# The temperature difference between the inside and outside faces in K\n",
+    "\n",
+    "# Calculation\n",
+    "Q_t=(L*h*k*delT*1000)/(t);# The rate of heat conduction in W\n",
+    "print\"The rate of heat conduction,Q_t=\",round(Q_t,0),\"W\"\"(or)\",round(Q_t/1000,0),\"kW)\"\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.9,PAGE NUMBER:10"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declartion\n",
+    "R_i=0.3;# The inside surface resistance in (m**2 K)/W\n",
+    "R_c=1/2.8;# The thermal conductance of plastered surface in (m**2 K)/W\n",
+    "R_o=0.05;# The outside surface resistance in (m**2 K)/W\n",
+    "\n",
+    "# Calculation\n",
+    "R_t=R_i+R_c+R_o;# The total thermal resistance in (m**2 K)/W\n",
+    "U=1/R_t;# The overall transmittance in W/(m**2 K)\n",
+    "print\"The overall transmittance,U=\",round(U,3),\" W/(m**2 K)\"\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 1.10,PAGE NUMBER:12"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declartion\n",
+    "T_f=3;# The temperature of fluid in °C\n",
+    "T_wi=11.5;# The temperature of water at inlet in °C\n",
+    "T_wo=6.4;# The temperature of water at outlet in °C\n",
+    "A=420;# The surface area in m**2\n",
+    "U=110;# The thermal transmittance in W/(m**2 K) \n",
+    "\n",
+    "# Calculation\n",
+    "delT_max=T_wi-T_f;# The maximum temperature difference in K\n",
+    "delT_min=T_wo-T_f;# The minimum temperature difference in K\n",
+    "LMTD=(delT_max-delT_min)/math.log(delT_max/delT_min);\n",
+    "Q_f=U*A*LMTD;# The amount of heat transfer in W\n",
+    "print\"The logarithmic mean temperature difference is\",round(LMTD,3),\"K\"\n",
+    "print\"The amount of heat transfer is\",round(Q_f,0),\"W (round off error)\",\"or\",round(Q_f/1000,0),\"kW\""
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2.ipynb
new file mode 100644
index 00000000..4710dde2
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2.ipynb
@@ -0,0 +1,71 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 2:The Refrigeration Cycle"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 2.1,PAGE NUMBER:21"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_l=0+273;# The required cooling temperature of room in °C\n",
+    "T_h=30+273;# The temperature of outside air in °C\n",
+    "T_e=-5+273;# The evaporating temperature of Refrigeration cycle in °C\n",
+    "T_c=35+273;# The Condensing temperature of Refrigeration cycle in °C\n",
+    "deltaT=5;# The temperature difference at the evaporator and the condenser in K\n",
+    "h_i=249.7;# Enthalpy of fl uid entering evaporator in kJ/kg\n",
+    "h_e=395.6;# Enthalpy of saturated vapour leaving evaporator in kJ/kg\n",
+    "h_sup=422.5;# Enthalpy of superheated vapour leaving compressor in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "CarnotCOP=T_l/(T_h-T_l);\n",
+    "print\"The Carnot COP for the process is\",round(CarnotCOP,1)\n",
+    "# For Refrigeration cycle,\n",
+    "CarnotCOP=T_e/(T_c-T_e);\n",
+    "print\"The Carnot COP for the refrigeration cycle is\",round(CarnotCOP,1)\n",
+    "# For R134a,\n",
+    "Q=h_e-h_i;# Cooling effect in kJ/kg\n",
+    "W_in=h_sup-h_e;# Compressor energy input in kJ/kg\n",
+    "COP=Q/W_in;# Ideal R134a vapour compression cycle COP\n",
+    "print\"The Carnot COP for the ideal vapour compression cycle  is\",round(COP,1)\n",
+    "\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21.ipynb
new file mode 100644
index 00000000..a769b073
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21.ipynb
@@ -0,0 +1,275 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 21:Air Treatment Fundamentals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.1,PAGE NUMBER:251"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m_a=68;# The mass flow rate of air in kg/s\n",
+    "T_1=16;# The temperature of air at inlet in °C\n",
+    "T_2=34;# The temperature of air at outlet in °C\n",
+    "T_win=85;# The temperature of hot water at inlet in °C\n",
+    "T_wout=74;# The temperature of hot water at outlet in °C\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=m_a*C_pa*(T_2-T_1);# Heat input in kW\n",
+    "m_w=Q/(C_pw*(T_win-T_wout));# The mass flow rate of water in kg/s\n",
+    "print\"\\nHeat input,Q=%4.0f kW \\nThe mass flow rate of water,Q=%2.0f kg/s\"%(Q,m_w)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.2,PAGE NUMBER:251"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q=500;# The amount of heat required for the building in kW\n",
+    "T=19;# The temperature at which air enters the heater coil in °C\n",
+    "m_a=68;# # The mass flow rate of air in kg/s\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "t=T+(Q/(m_a*C_pa));# The air supply temperature in °C\n",
+    "print\"The air-supply temperature,t=%2.1f°C\"%t"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.3,PAGE NUMBER:254"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_ra=21;# The temperature of the returning air \n",
+    "H=50;# % saturation\n",
+    "T_d=28;# The dry bulb temperature in °C\n",
+    "T_w=20;# The wet bulb temperature in °C\n",
+    "m_a=20;# The mass flow rate of returning air in kg/s\n",
+    "m_b=3;# The mass flow rate of outside air in kg/s\n",
+    "x_ra=0.0079;# The moisture content in kg/kg\n",
+    "x_oa=0.0111;# The moisture content in kg/kg\n",
+    "h_a=41.8;# The enthalpy in kJ/kg\n",
+    "h_b=56.6;# The enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "# Method (b)\n",
+    "t_c=((T_ra*m_a)+(T_d*m_b))/(m_a+m_b);# °C\n",
+    "g_c=((x_ra*m_a)+(x_oa*m_b))/(m_a+m_b);# kg/kg\n",
+    "h_c=((h_a*m_a)+(h_a*m_b))/(m_a+m_b);# kJ/kg dry air\n",
+    "print\"\\nThe condition of the mixture,t_c=%2.1f°C\"%t_c\n",
+    "print\"\\n                             g_c=%0.4f kg/kg\"%g_c\n",
+    "print\"\\n                             h_c=%2.1f kJ/kg dry air\"%h_c"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.5,PAGE NUMBER:257"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_s=100;# The temperature of steam in °C\n",
+    "T_d=21;# The dry bulb temperature in °C\n",
+    "H=50;#  % saturation\n",
+    "x_ab=0.0079;# Moisture content of air before in kg/kg\n",
+    "x_a=0.0067;# Moisture added in kg/kg\n",
+    "C_ps=1.972;# The specific heat capacity of the steam in kJ/kg°C\n",
+    "C_pa=1.006;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "x=x_ab+x_a;# Final moisture content in kg/kg\n",
+    "t=((x_a*C_ps*T_s)+(C_pa*T_d))/(((x_a*C_ps)+(C_pa)));# The final dry bulb temperature in °C\n",
+    "print\"\\nFinal moisture content=%0.4f kg/kg \\nThe final dry bulb temperature,t=%2.2f°C\"%(x,t)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.6,PAGE NUMBER:259"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d1=23;# The dry bulb temperature in °C\n",
+    "T_w=5;# The temperature of water in °C\n",
+    "H=50;#  % saturation\n",
+    "n_s=0.7;# Saturation efficiency in %\n",
+    "x_a=0.0089;# Moisture content in kg/kg\n",
+    "x_b=0.0054;# Moisture content in kg/kg\n",
+    "\n",
+    "# Calculation\n",
+    "#(a)\n",
+    "print\"(a) By construction on the chart ( Figure 21.7 ), the final condition is 10.4°C dry bulb,82% saturation\"\n",
+    "#(b)\n",
+    "T_d2=T_d1-(n_s*(T_d1-T_w));# The final dry bulb temperature in °C\n",
+    "x_f=x_a-(n_s*(x_a-x_b));# kg/kg\n",
+    "print\"\\n(b)The final condition,\\n   The final dry bulb temperature=%2.1f°C \\n   The moisture content=%0.5f kg/kg\"%(T_d2,x_f)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.7,PAGE NUMBER:259"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m_w=4;# The mass of water in kg\n",
+    "m_a=1;# The mass of air in kg\n",
+    "h_ab=45.79;# Enthalpy of air before in kJ/kg\n",
+    "h_aa=26.7;# Enthalpy of air after in kJ/kg\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q_l=h_ab-h_aa;# Heat lost per kilogram air in kJ\n",
+    "Q_g=Q_l/m_w;# Heat gain per kilogram water in kJ\n",
+    "dT=Q_g/C_pw;# Temperature rise of water in K\n",
+    "print\"Temperature rise of water=%1.0f K\"%dT\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.8,PAGE NUMBER:261"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d1=24;# The dry bulb temperature in °C\n",
+    "T_d2=7;# The dry bulb temperature in °C\n",
+    "H=45;#  % saturation\n",
+    "cf=0.78;# Contact factor\n",
+    "h_1=45.85;# The enthalpy in kJ/kg\n",
+    "h_2=22.72;# The enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "#(a) By construction on the chart ( Figure 21.9 ), 10.7°C dry bulb, 85% saturation.\n",
+    "#(b) By calculation, the dry bulb will drop 78% of 24 to 7°C:\n",
+    "dT=T_d1-(cf*(T_d1-T_d2));# The drop in dry bulb temperature in °C\n",
+    "dh=h_1-(cf*(h_1-h_2));# The drop in enthalpy in kJ/kg\n",
+    "print\"\\nThe drop in dry bulb temperature=%2.1f°C \\nThe drop in enthlpy=%2.2f kJ/kg\"%(dT,dh)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.10,PAGE NUMBER:262"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=23;# The dry bulb temperature in °C\n",
+    "H=40;# % saturation\n",
+    "SH=36;# The sensible heat to be removed in kW\n",
+    "LH=14;# The latent heat in kW\n",
+    "\n",
+    "# Calculation\n",
+    "# Plotting on the chart ( Figure 21.10 ) from 23°C/40% and using the ratio\n",
+    "R=SH/(SH+LH);\n",
+    "print\"The process line meets the saturation curve at - 1°C, giving the ADP (which meansthat condensate will collect on the fins as frost).\"\n",
+    "print\"Taking the ‘ off ’ condition at 5°C dry bulb and measuring the proportion along theprocess line gives a coil contact factor of 75%.\"\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21_CbiJJQV.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21_CbiJJQV.ipynb
new file mode 100644
index 00000000..a769b073
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER21_CbiJJQV.ipynb
@@ -0,0 +1,275 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 21:Air Treatment Fundamentals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.1,PAGE NUMBER:251"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m_a=68;# The mass flow rate of air in kg/s\n",
+    "T_1=16;# The temperature of air at inlet in °C\n",
+    "T_2=34;# The temperature of air at outlet in °C\n",
+    "T_win=85;# The temperature of hot water at inlet in °C\n",
+    "T_wout=74;# The temperature of hot water at outlet in °C\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=m_a*C_pa*(T_2-T_1);# Heat input in kW\n",
+    "m_w=Q/(C_pw*(T_win-T_wout));# The mass flow rate of water in kg/s\n",
+    "print\"\\nHeat input,Q=%4.0f kW \\nThe mass flow rate of water,Q=%2.0f kg/s\"%(Q,m_w)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.2,PAGE NUMBER:251"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q=500;# The amount of heat required for the building in kW\n",
+    "T=19;# The temperature at which air enters the heater coil in °C\n",
+    "m_a=68;# # The mass flow rate of air in kg/s\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "t=T+(Q/(m_a*C_pa));# The air supply temperature in °C\n",
+    "print\"The air-supply temperature,t=%2.1f°C\"%t"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.3,PAGE NUMBER:254"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_ra=21;# The temperature of the returning air \n",
+    "H=50;# % saturation\n",
+    "T_d=28;# The dry bulb temperature in °C\n",
+    "T_w=20;# The wet bulb temperature in °C\n",
+    "m_a=20;# The mass flow rate of returning air in kg/s\n",
+    "m_b=3;# The mass flow rate of outside air in kg/s\n",
+    "x_ra=0.0079;# The moisture content in kg/kg\n",
+    "x_oa=0.0111;# The moisture content in kg/kg\n",
+    "h_a=41.8;# The enthalpy in kJ/kg\n",
+    "h_b=56.6;# The enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "# Method (b)\n",
+    "t_c=((T_ra*m_a)+(T_d*m_b))/(m_a+m_b);# °C\n",
+    "g_c=((x_ra*m_a)+(x_oa*m_b))/(m_a+m_b);# kg/kg\n",
+    "h_c=((h_a*m_a)+(h_a*m_b))/(m_a+m_b);# kJ/kg dry air\n",
+    "print\"\\nThe condition of the mixture,t_c=%2.1f°C\"%t_c\n",
+    "print\"\\n                             g_c=%0.4f kg/kg\"%g_c\n",
+    "print\"\\n                             h_c=%2.1f kJ/kg dry air\"%h_c"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.5,PAGE NUMBER:257"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_s=100;# The temperature of steam in °C\n",
+    "T_d=21;# The dry bulb temperature in °C\n",
+    "H=50;#  % saturation\n",
+    "x_ab=0.0079;# Moisture content of air before in kg/kg\n",
+    "x_a=0.0067;# Moisture added in kg/kg\n",
+    "C_ps=1.972;# The specific heat capacity of the steam in kJ/kg°C\n",
+    "C_pa=1.006;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "x=x_ab+x_a;# Final moisture content in kg/kg\n",
+    "t=((x_a*C_ps*T_s)+(C_pa*T_d))/(((x_a*C_ps)+(C_pa)));# The final dry bulb temperature in °C\n",
+    "print\"\\nFinal moisture content=%0.4f kg/kg \\nThe final dry bulb temperature,t=%2.2f°C\"%(x,t)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.6,PAGE NUMBER:259"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d1=23;# The dry bulb temperature in °C\n",
+    "T_w=5;# The temperature of water in °C\n",
+    "H=50;#  % saturation\n",
+    "n_s=0.7;# Saturation efficiency in %\n",
+    "x_a=0.0089;# Moisture content in kg/kg\n",
+    "x_b=0.0054;# Moisture content in kg/kg\n",
+    "\n",
+    "# Calculation\n",
+    "#(a)\n",
+    "print\"(a) By construction on the chart ( Figure 21.7 ), the final condition is 10.4°C dry bulb,82% saturation\"\n",
+    "#(b)\n",
+    "T_d2=T_d1-(n_s*(T_d1-T_w));# The final dry bulb temperature in °C\n",
+    "x_f=x_a-(n_s*(x_a-x_b));# kg/kg\n",
+    "print\"\\n(b)The final condition,\\n   The final dry bulb temperature=%2.1f°C \\n   The moisture content=%0.5f kg/kg\"%(T_d2,x_f)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.7,PAGE NUMBER:259"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "m_w=4;# The mass of water in kg\n",
+    "m_a=1;# The mass of air in kg\n",
+    "h_ab=45.79;# Enthalpy of air before in kJ/kg\n",
+    "h_aa=26.7;# Enthalpy of air after in kJ/kg\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q_l=h_ab-h_aa;# Heat lost per kilogram air in kJ\n",
+    "Q_g=Q_l/m_w;# Heat gain per kilogram water in kJ\n",
+    "dT=Q_g/C_pw;# Temperature rise of water in K\n",
+    "print\"Temperature rise of water=%1.0f K\"%dT\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.8,PAGE NUMBER:261"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d1=24;# The dry bulb temperature in °C\n",
+    "T_d2=7;# The dry bulb temperature in °C\n",
+    "H=45;#  % saturation\n",
+    "cf=0.78;# Contact factor\n",
+    "h_1=45.85;# The enthalpy in kJ/kg\n",
+    "h_2=22.72;# The enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "#(a) By construction on the chart ( Figure 21.9 ), 10.7°C dry bulb, 85% saturation.\n",
+    "#(b) By calculation, the dry bulb will drop 78% of 24 to 7°C:\n",
+    "dT=T_d1-(cf*(T_d1-T_d2));# The drop in dry bulb temperature in °C\n",
+    "dh=h_1-(cf*(h_1-h_2));# The drop in enthalpy in kJ/kg\n",
+    "print\"\\nThe drop in dry bulb temperature=%2.1f°C \\nThe drop in enthlpy=%2.2f kJ/kg\"%(dT,dh)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 21.10,PAGE NUMBER:262"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=23;# The dry bulb temperature in °C\n",
+    "H=40;# % saturation\n",
+    "SH=36;# The sensible heat to be removed in kW\n",
+    "LH=14;# The latent heat in kW\n",
+    "\n",
+    "# Calculation\n",
+    "# Plotting on the chart ( Figure 21.10 ) from 23°C/40% and using the ratio\n",
+    "R=SH/(SH+LH);\n",
+    "print\"The process line meets the saturation curve at - 1°C, giving the ADP (which meansthat condensate will collect on the fins as frost).\"\n",
+    "print\"Taking the ‘ off ’ condition at 5°C dry bulb and measuring the proportion along theprocess line gives a coil contact factor of 75%.\"\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22.ipynb
new file mode 100644
index 00000000..eb85362f
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22.ipynb
@@ -0,0 +1,116 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 22:Practical Air Treatment Cycles"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Example 22.1,PAGE NUMBER:270"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=37;# The dry bulb temperature of air in °C\n",
+    "H=24;# % saturation\n",
+    "n_s=75;# Saturation efficiency in %\n",
+    "h=62.67;# The entering enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "# By construction on the chart, or from tables, the ultimate saturation condition would be 21.5°C, and 75% of the drop from 37°C to 21.5°C gives a fi nal dry bulb of 25.4°C.\n",
+    "h_fg=2425;# The average latent heat of water over the working range in kJ/kg\n",
+    "q=(h_fg)**-1;# The amount of water to be evaporated in kg/(s kW)\n",
+    "print\"The amount of water to be evaporated is %0.0e kg/(s kW)\"%q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 22.2,PAGE NUMBER:271"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=37;# The dry bulb temperature of air in °C\n",
+    "T_w=25.4;# The cooling temperature of water in °C\n",
+    "cf=0.80;# Contact factor\n",
+    "\n",
+    "# Calculation\n",
+    "T_df=T_d-(cf*(T_d-T_w));# The dry bulb temperature (final) in °C\n",
+    "print\"\\nThe dry bulb temperature (final)=%2.1f°C (point D , Figure 22.4b )\"%T_df\n",
+    "print\"\\nThe wet bulb is now 18.9°C and the enthalpy is 53 kJ/kg.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 22.3,PAGE NUMBER:271"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=26;# The dry bulb temperature of air in °C\n",
+    "T_w=20;# The wet bulb temperature of water in °C\n",
+    "T_win=29;# The temperature of water at inlet in °C\n",
+    "T_wout=24;# The temperature of water at outlet in °C\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=C_pw*(T_win-T_wout);# Heat from water in kJ/kg\n",
+    "h_ain=57.1;# Enthalpy of entering air in kJ/kg\n",
+    "h_aout=78.1;# Enthalpy of leaving air in kJ/kg\n",
+    "print\"\\nHeat from water=%2.0f kJ/kg \\nEnthalpy of entering air=57.1 kJ/kg \\nEnthalpy of leaving air=78.1 kJ/kg\"%Q\n",
+    "print\"From the chart, the air leaves at approximately 25.7°C dry bulb.\""
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22_A90BBe5.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22_A90BBe5.ipynb
new file mode 100644
index 00000000..eb85362f
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER22_A90BBe5.ipynb
@@ -0,0 +1,116 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 22:Practical Air Treatment Cycles"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Example 22.1,PAGE NUMBER:270"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=37;# The dry bulb temperature of air in °C\n",
+    "H=24;# % saturation\n",
+    "n_s=75;# Saturation efficiency in %\n",
+    "h=62.67;# The entering enthalpy in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "# By construction on the chart, or from tables, the ultimate saturation condition would be 21.5°C, and 75% of the drop from 37°C to 21.5°C gives a fi nal dry bulb of 25.4°C.\n",
+    "h_fg=2425;# The average latent heat of water over the working range in kJ/kg\n",
+    "q=(h_fg)**-1;# The amount of water to be evaporated in kg/(s kW)\n",
+    "print\"The amount of water to be evaporated is %0.0e kg/(s kW)\"%q"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 22.2,PAGE NUMBER:271"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=37;# The dry bulb temperature of air in °C\n",
+    "T_w=25.4;# The cooling temperature of water in °C\n",
+    "cf=0.80;# Contact factor\n",
+    "\n",
+    "# Calculation\n",
+    "T_df=T_d-(cf*(T_d-T_w));# The dry bulb temperature (final) in °C\n",
+    "print\"\\nThe dry bulb temperature (final)=%2.1f°C (point D , Figure 22.4b )\"%T_df\n",
+    "print\"\\nThe wet bulb is now 18.9°C and the enthalpy is 53 kJ/kg.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 22.3,PAGE NUMBER:271"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "T_d=26;# The dry bulb temperature of air in °C\n",
+    "T_w=20;# The wet bulb temperature of water in °C\n",
+    "T_win=29;# The temperature of water at inlet in °C\n",
+    "T_wout=24;# The temperature of water at outlet in °C\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=C_pw*(T_win-T_wout);# Heat from water in kJ/kg\n",
+    "h_ain=57.1;# Enthalpy of entering air in kJ/kg\n",
+    "h_aout=78.1;# Enthalpy of leaving air in kJ/kg\n",
+    "print\"\\nHeat from water=%2.0f kJ/kg \\nEnthalpy of entering air=57.1 kJ/kg \\nEnthalpy of leaving air=78.1 kJ/kg\"%Q\n",
+    "print\"From the chart, the air leaves at approximately 25.7°C dry bulb.\""
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23.ipynb
new file mode 100644
index 00000000..ff7d9550
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23.ipynb
@@ -0,0 +1,130 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 23:Air-Conditioning Load Estimation"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.1,PAGE NUMBER:275"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "R_si=0.3;# The inside resistance in (m**2 K)/W\n",
+    "R_1=0.040/0.09;# The thermal resistance of concrete panels in  (m**2 K)/W\n",
+    "R_2=0.050/0.037;# The thermal resistance of insulation in  (m**2 K)/W\n",
+    "R_3=0.012/0.16;# The thermal resistance of plaster board in  (m**2 K)/W\n",
+    "R_so=0.07;# The outside resistance in (m**2 K)/W\n",
+    "\n",
+    "#Calculation\n",
+    "U=1/(R_si+R_1+R_2+R_3+R_so);# U factor in W/(m**2 K)\n",
+    "print\"U factor=%0.2f W/(m**2 K)\"%U"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.2,PAGE NUMBER:278"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "T_d1=21;# The dry bulb temperature of air in °C\n",
+    "H=45;# % saturation\n",
+    "T_d2=27;# The dry bulb temperature of air in °C\n",
+    "T_wb1=20;# The wet bulb temperature of air in °C\n",
+    "m=1.35;# The mass flow rate of air in kg/s\n",
+    "C_pa=1.006;# The specific heat capacity of air in kJ/kg.K\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "#Calculation\n",
+    " # 1.Total heat:\n",
+    "h_2=57.00;# Enthalpy at 27°C DB, 20°C WB in kJ/kg\n",
+    "h_1=39.08;# Enthalpy at 21°C DB, 45% sat in kJ/kg\n",
+    "dh=17.92;# Heat to be removed in kJ/kg\n",
+    "Q_t=dh*m;# Total heat in kW\n",
+    "print\"Total heat,Q_t=%2.1f kW\"% Q_t\n",
+    "\n",
+    "# 2.Latent heat:\n",
+    "x_2=0.0117;# Moisture at 27°C DB, 20°C WB in kg/kg\n",
+    "x_1=0.0070;# Moisture at 21°C DB, 45% sat in kg/kg\n",
+    "dx=x_2-x_1;# Moisture to be removed in kg/kg\n",
+    "Q_l=dx*m*2440;# Latent heat in kW\n",
+    "print\"Latent heat,Q_l=%2.1f kW\"% Q_l\n",
+    "\n",
+    "# 3.Sensible heat:\n",
+    "Q_s=(C_pa+((C_pw*x_2)))*(T_d2-T_d1)*m;# Sensible heat in kW\n",
+    "print\"Sensible heat,Q_s=%1.1f kW\"% Q_s"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.3,PAGE NUMBER:280"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "Q_tl=15;# Total lighting load\n",
+    "P_ra=90;# % of load taken from return air\n",
+    "P_a=25;# % of load rejected to ambient\n",
+    "\n",
+    "#Calculation\n",
+    "Q_ra=Q_tl*(P_ra*10**-2);# Picked up by return air in kW\n",
+    "Q_a=Q_ra*(P_a*10**-2);# Rejected to ambient in kW\n",
+    "Q_net=Q_tl-Q_a;# Net room load in kW \n",
+    "print\"\\nNet room load=%2.3f kW\"%Q_net"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23_epZvlzC.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23_epZvlzC.ipynb
new file mode 100644
index 00000000..ff7d9550
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER23_epZvlzC.ipynb
@@ -0,0 +1,130 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 23:Air-Conditioning Load Estimation"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.1,PAGE NUMBER:275"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "R_si=0.3;# The inside resistance in (m**2 K)/W\n",
+    "R_1=0.040/0.09;# The thermal resistance of concrete panels in  (m**2 K)/W\n",
+    "R_2=0.050/0.037;# The thermal resistance of insulation in  (m**2 K)/W\n",
+    "R_3=0.012/0.16;# The thermal resistance of plaster board in  (m**2 K)/W\n",
+    "R_so=0.07;# The outside resistance in (m**2 K)/W\n",
+    "\n",
+    "#Calculation\n",
+    "U=1/(R_si+R_1+R_2+R_3+R_so);# U factor in W/(m**2 K)\n",
+    "print\"U factor=%0.2f W/(m**2 K)\"%U"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.2,PAGE NUMBER:278"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "T_d1=21;# The dry bulb temperature of air in °C\n",
+    "H=45;# % saturation\n",
+    "T_d2=27;# The dry bulb temperature of air in °C\n",
+    "T_wb1=20;# The wet bulb temperature of air in °C\n",
+    "m=1.35;# The mass flow rate of air in kg/s\n",
+    "C_pa=1.006;# The specific heat capacity of air in kJ/kg.K\n",
+    "C_pw=4.187;# The specific heat capacity of water in kJ/kg.K\n",
+    "\n",
+    "#Calculation\n",
+    " # 1.Total heat:\n",
+    "h_2=57.00;# Enthalpy at 27°C DB, 20°C WB in kJ/kg\n",
+    "h_1=39.08;# Enthalpy at 21°C DB, 45% sat in kJ/kg\n",
+    "dh=17.92;# Heat to be removed in kJ/kg\n",
+    "Q_t=dh*m;# Total heat in kW\n",
+    "print\"Total heat,Q_t=%2.1f kW\"% Q_t\n",
+    "\n",
+    "# 2.Latent heat:\n",
+    "x_2=0.0117;# Moisture at 27°C DB, 20°C WB in kg/kg\n",
+    "x_1=0.0070;# Moisture at 21°C DB, 45% sat in kg/kg\n",
+    "dx=x_2-x_1;# Moisture to be removed in kg/kg\n",
+    "Q_l=dx*m*2440;# Latent heat in kW\n",
+    "print\"Latent heat,Q_l=%2.1f kW\"% Q_l\n",
+    "\n",
+    "# 3.Sensible heat:\n",
+    "Q_s=(C_pa+((C_pw*x_2)))*(T_d2-T_d1)*m;# Sensible heat in kW\n",
+    "print\"Sensible heat,Q_s=%1.1f kW\"% Q_s"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 23.3,PAGE NUMBER:280"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "#Variable declaration\n",
+    "Q_tl=15;# Total lighting load\n",
+    "P_ra=90;# % of load taken from return air\n",
+    "P_a=25;# % of load rejected to ambient\n",
+    "\n",
+    "#Calculation\n",
+    "Q_ra=Q_tl*(P_ra*10**-2);# Picked up by return air in kW\n",
+    "Q_a=Q_ra*(P_a*10**-2);# Rejected to ambient in kW\n",
+    "Q_net=Q_tl-Q_a;# Net room load in kW \n",
+    "print\"\\nNet room load=%2.3f kW\"%Q_net"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24.ipynb
new file mode 100644
index 00000000..66471240
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24.ipynb
@@ -0,0 +1,115 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 24:Air Movement"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.1,PAGE NUMBER:281"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Z=4500;# Altitude in m\n",
+    "p=575;# mbar barometric pressure\n",
+    "t=-10;# Temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "rho=1.2*(p/1013.25)*((273.15+20)/(273.15+t));# The density of dry air in kg/m**3\n",
+    "print\"The density of dry air,rho=%0.2f kg/m**3\"%rho"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.2,PAGE NUMBER:282"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "V=1;# The volume of air in m**3\n",
+    "t=20;# The dry bulb temperature in °C\n",
+    "H=60;# % saturation\n",
+    "p=101.325;# The pressure in kPa\n",
+    "v=7;# The velocity in m/s\n",
+    "v_s=0.8419;# The specific volume in m**3/kg\n",
+    "\n",
+    "# Calculation\n",
+    "m=V/v_s;# Mass in kg\n",
+    "Ke=(m*v**2)/2;# Kinetic energy in kg/(m s**2)\n",
+    "print\"Kinetic energy=%2.1f kg/(m s**2)\"%Ke"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.3,PAGE NUMBER:296"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "v_e=8;# The entering velocity of air in m/s\n",
+    "v_l=5.5;# The leaving velocity of air in m/s\n",
+    "fl=20;# Friction losses in %\n",
+    "m=1.2;# Masss in kg\n",
+    "\n",
+    "# Calculation\n",
+    "P_e=(m*v_e**2)/2;# Velocity pressure entering expansion in Pa\n",
+    "P_l=(m*v_l**2)/2;# Velocity pressure leaving expansion in Pa\n",
+    "FL=fl*10**-2*(P_e-P_l);# Friction losses in Pa\n",
+    "Sr=(1-(fl*10**-2))*(P_e-P_l);# Static regain in Pa\n",
+    "print\"The amount of Static regain=%2.1f Pa\"%Sr"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24_ZrVZ9ht.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24_ZrVZ9ht.ipynb
new file mode 100644
index 00000000..66471240
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER24_ZrVZ9ht.ipynb
@@ -0,0 +1,115 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 24:Air Movement"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.1,PAGE NUMBER:281"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Z=4500;# Altitude in m\n",
+    "p=575;# mbar barometric pressure\n",
+    "t=-10;# Temperature in °C\n",
+    "\n",
+    "# Calculation\n",
+    "rho=1.2*(p/1013.25)*((273.15+20)/(273.15+t));# The density of dry air in kg/m**3\n",
+    "print\"The density of dry air,rho=%0.2f kg/m**3\"%rho"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.2,PAGE NUMBER:282"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "V=1;# The volume of air in m**3\n",
+    "t=20;# The dry bulb temperature in °C\n",
+    "H=60;# % saturation\n",
+    "p=101.325;# The pressure in kPa\n",
+    "v=7;# The velocity in m/s\n",
+    "v_s=0.8419;# The specific volume in m**3/kg\n",
+    "\n",
+    "# Calculation\n",
+    "m=V/v_s;# Mass in kg\n",
+    "Ke=(m*v**2)/2;# Kinetic energy in kg/(m s**2)\n",
+    "print\"Kinetic energy=%2.1f kg/(m s**2)\"%Ke"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 24.3,PAGE NUMBER:296"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "v_e=8;# The entering velocity of air in m/s\n",
+    "v_l=5.5;# The leaving velocity of air in m/s\n",
+    "fl=20;# Friction losses in %\n",
+    "m=1.2;# Masss in kg\n",
+    "\n",
+    "# Calculation\n",
+    "P_e=(m*v_e**2)/2;# Velocity pressure entering expansion in Pa\n",
+    "P_l=(m*v_l**2)/2;# Velocity pressure leaving expansion in Pa\n",
+    "FL=fl*10**-2*(P_e-P_l);# Friction losses in Pa\n",
+    "Sr=(1-(fl*10**-2))*(P_e-P_l);# Static regain in Pa\n",
+    "print\"The amount of Static regain=%2.1f Pa\"%Sr"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25.ipynb
new file mode 100644
index 00000000..6dde7780
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25.ipynb
@@ -0,0 +1,169 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 25:Air-Conditioning Methods"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.1,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable Declaration\n",
+    "T_d=21;# The dry bulb temperature in °C\n",
+    "Q=14;# Internal load in kW\n",
+    "H=50;# % saturation\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "T_ain=12;# The inlet air temperature in °C \n",
+    "C_p=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=T_d-T_ain;# Air temperature rise through room in K\n",
+    "m=Q/(deltaT*C_p);# Air flow for sensible heat in kg/s\n",
+    "x=0.007857;# Moisture content of room air, 21, 50%\n",
+    "x_p=Q_l/(2440*m);# Moisture to pick up\n",
+    "x_ain=x-x_p;# Moisture content of entering air \n",
+    "print\"\\nAir flow for sensible heat=%1.3f kg/s \\nMoisture content of entering air=%0.5f\"%(m,x_ain)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.2,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "# From example 25.1\n",
+    "Q_i=14;# Internal load in kW\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "Q_f=0.9;# The fan motor power in kW\n",
+    "T_win=5;# The temperature of water at inlet in °C \n",
+    "T_wout=10.5;# The temperature of water at outlet in °C \n",
+    "C_pw=4.19;# The specific heat capacity in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=Q_i+Q_l+Q_f;# Total cooling load in kW\n",
+    "m_w=Q/(C_pw*(T_wout-T_win));# Mass water flow in kg/s\n",
+    "print\"\\nMass water flow=%0.2f kg/s\"%m_w"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.3,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "# From example 25.2\n",
+    "Q=16.4;# Total load in kW\n",
+    "T_in=33;# The temperature at liquid R134a enters the expansion valve in °C \n",
+    "T_out=9;# The temperature at liquid  R134a leaves the cooler in °C \n",
+    "T_e=5;#  The temperature at which liquid  R134a evaporates in °C \n",
+    "\n",
+    "# Calculation\n",
+    "h_v=405.23;# Enthalpy of R134a,superheated to 9 C in kJ/kg\n",
+    "h_f=246.71;# Enthalpy of liquid R134a at 33 C in kJ/kg\n",
+    "Re=h_v-h_f;# Refrigerating effect in kJ/kg\n",
+    "m_r=Q/Re;# Required refrigerant mass flow in kg/s\n",
+    "print\"Required refrigerant mass flow=%0.3f kg/s\"%m_r\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## EXAMPLE 25.4,PAGE NUMBER:306"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "T_d1=13;# The dry bulb temperature in °C \n",
+    "m_a=0.4;# The flow rate of primary air in kg/s\n",
+    "T_win=12;# The temperature of water at inlet in °C \n",
+    "T_wout=16;# The temperature of water at outlet in °C \n",
+    "H=72;# % saturation\n",
+    "T_d2=21;# The dry bulb temperature in °C \n",
+    "# From example 25.1\n",
+    "Q_i=14;# Internal load in kW\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "C_pw=4.19;# The specific heat capacity in kJ/kg.K\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "x_a=0.006744;# Moisture in primary air, 13 C DB, 72% sat\n",
+    "x_r=Q_l/(2440*m_a);# Moisture removed in kg/kg\n",
+    "x_rise=x_a+x_r;# Moisture in room air will rise to in kg/kg\n",
+    "# which corresponds to a room condition of 21°C dry bulb, 53% saturation\n",
+    "Q_a=m_a*C_pa*(T_d2-T_d1);# Sensible heat removed by primary air in kW\n",
+    "Q_w=Q_i-Q_a;# Heat to be removed by water in kW\n",
+    "m_w=Q_w/(C_pw*(T_wout-T_win));# Mass water flow in kg/s\n",
+    "print\"\\nMass water flow=%0.2f kg/s\"%m_w"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25_1DX8OSW.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25_1DX8OSW.ipynb
new file mode 100644
index 00000000..6dde7780
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER25_1DX8OSW.ipynb
@@ -0,0 +1,169 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 25:Air-Conditioning Methods"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.1,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable Declaration\n",
+    "T_d=21;# The dry bulb temperature in °C\n",
+    "Q=14;# Internal load in kW\n",
+    "H=50;# % saturation\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "T_ain=12;# The inlet air temperature in °C \n",
+    "C_p=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=T_d-T_ain;# Air temperature rise through room in K\n",
+    "m=Q/(deltaT*C_p);# Air flow for sensible heat in kg/s\n",
+    "x=0.007857;# Moisture content of room air, 21, 50%\n",
+    "x_p=Q_l/(2440*m);# Moisture to pick up\n",
+    "x_ain=x-x_p;# Moisture content of entering air \n",
+    "print\"\\nAir flow for sensible heat=%1.3f kg/s \\nMoisture content of entering air=%0.5f\"%(m,x_ain)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.2,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "# From example 25.1\n",
+    "Q_i=14;# Internal load in kW\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "Q_f=0.9;# The fan motor power in kW\n",
+    "T_win=5;# The temperature of water at inlet in °C \n",
+    "T_wout=10.5;# The temperature of water at outlet in °C \n",
+    "C_pw=4.19;# The specific heat capacity in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "Q=Q_i+Q_l+Q_f;# Total cooling load in kW\n",
+    "m_w=Q/(C_pw*(T_wout-T_win));# Mass water flow in kg/s\n",
+    "print\"\\nMass water flow=%0.2f kg/s\"%m_w"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 25.3,PAGE NUMBER:305"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "# From example 25.2\n",
+    "Q=16.4;# Total load in kW\n",
+    "T_in=33;# The temperature at liquid R134a enters the expansion valve in °C \n",
+    "T_out=9;# The temperature at liquid  R134a leaves the cooler in °C \n",
+    "T_e=5;#  The temperature at which liquid  R134a evaporates in °C \n",
+    "\n",
+    "# Calculation\n",
+    "h_v=405.23;# Enthalpy of R134a,superheated to 9 C in kJ/kg\n",
+    "h_f=246.71;# Enthalpy of liquid R134a at 33 C in kJ/kg\n",
+    "Re=h_v-h_f;# Refrigerating effect in kJ/kg\n",
+    "m_r=Q/Re;# Required refrigerant mass flow in kg/s\n",
+    "print\"Required refrigerant mass flow=%0.3f kg/s\"%m_r\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## EXAMPLE 25.4,PAGE NUMBER:306"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "T_d1=13;# The dry bulb temperature in °C \n",
+    "m_a=0.4;# The flow rate of primary air in kg/s\n",
+    "T_win=12;# The temperature of water at inlet in °C \n",
+    "T_wout=16;# The temperature of water at outlet in °C \n",
+    "H=72;# % saturation\n",
+    "T_d2=21;# The dry bulb temperature in °C \n",
+    "# From example 25.1\n",
+    "Q_i=14;# Internal load in kW\n",
+    "Q_l=1.5;# Latent heat gain in kW\n",
+    "C_pw=4.19;# The specific heat capacity in kJ/kg.K\n",
+    "C_pa=1.02;# The specific heat capacity of air in kJ/kg.K\n",
+    "\n",
+    "# Calculation\n",
+    "x_a=0.006744;# Moisture in primary air, 13 C DB, 72% sat\n",
+    "x_r=Q_l/(2440*m_a);# Moisture removed in kg/kg\n",
+    "x_rise=x_a+x_r;# Moisture in room air will rise to in kg/kg\n",
+    "# which corresponds to a room condition of 21°C dry bulb, 53% saturation\n",
+    "Q_a=m_a*C_pa*(T_d2-T_d1);# Sensible heat removed by primary air in kW\n",
+    "Q_w=Q_i-Q_a;# Heat to be removed by water in kW\n",
+    "m_w=Q_w/(C_pw*(T_wout-T_win));# Mass water flow in kg/s\n",
+    "print\"\\nMass water flow=%0.2f kg/s\"%m_w"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29.ipynb
new file mode 100644
index 00000000..9ccca88a
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29.ipynb
@@ -0,0 +1,64 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 29:Commissioning and Maintenance"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 29.1,PAGE NUMBER:347"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "T_e=3;# The evaporating temperature in °C\n",
+    "T_in=20;# The temperature of air entering coil in °C\n",
+    "T_out=11;# The temperature of air off coil at full air flow in °C\n",
+    "T_c=35;# The condensing temperature in °C\n",
+    "af=(1-0.15);# The reduced air flow \n",
+    "\n",
+    "# Calculation\n",
+    "LMTD=((T_in-T_e)-(T_out-T_e))/math.log((T_in-T_e)/(T_out-T_e));# K\n",
+    "T_aoff=T_in-(T_in-T_out)/af;# Air off coil at 85% air flow (°C)\n",
+    "Cp=(af)**0.8;# Coil performance at 85% air flow (°C)\n",
+    "LMTD_85=LMTD/Cp;# LMTD at 85% air flow in K\n",
+    "print\"\\nLMTD at 85 percentage air flow=%2.1f K(error)\"%LMTD_85"
+   ]
+  }
+ ],
+ "metadata": {
+  "celltoolbar": "Raw Cell Format",
+  "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29_BRfETw7.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29_BRfETw7.ipynb
new file mode 100644
index 00000000..9ccca88a
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER29_BRfETw7.ipynb
@@ -0,0 +1,64 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 29:Commissioning and Maintenance"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 29.1,PAGE NUMBER:347"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "# Variable declaration\n",
+    "T_e=3;# The evaporating temperature in °C\n",
+    "T_in=20;# The temperature of air entering coil in °C\n",
+    "T_out=11;# The temperature of air off coil at full air flow in °C\n",
+    "T_c=35;# The condensing temperature in °C\n",
+    "af=(1-0.15);# The reduced air flow \n",
+    "\n",
+    "# Calculation\n",
+    "LMTD=((T_in-T_e)-(T_out-T_e))/math.log((T_in-T_e)/(T_out-T_e));# K\n",
+    "T_aoff=T_in-(T_in-T_out)/af;# Air off coil at 85% air flow (°C)\n",
+    "Cp=(af)**0.8;# Coil performance at 85% air flow (°C)\n",
+    "LMTD_85=LMTD/Cp;# LMTD at 85% air flow in K\n",
+    "print\"\\nLMTD at 85 percentage air flow=%2.1f K(error)\"%LMTD_85"
+   ]
+  }
+ ],
+ "metadata": {
+  "celltoolbar": "Raw Cell Format",
+  "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2_3QlBwiq.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2_3QlBwiq.ipynb
new file mode 100644
index 00000000..4710dde2
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER2_3QlBwiq.ipynb
@@ -0,0 +1,71 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 2:The Refrigeration Cycle"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## EXAMPLE 2.1,PAGE NUMBER:21"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable Declaration\n",
+    "T_l=0+273;# The required cooling temperature of room in °C\n",
+    "T_h=30+273;# The temperature of outside air in °C\n",
+    "T_e=-5+273;# The evaporating temperature of Refrigeration cycle in °C\n",
+    "T_c=35+273;# The Condensing temperature of Refrigeration cycle in °C\n",
+    "deltaT=5;# The temperature difference at the evaporator and the condenser in K\n",
+    "h_i=249.7;# Enthalpy of fl uid entering evaporator in kJ/kg\n",
+    "h_e=395.6;# Enthalpy of saturated vapour leaving evaporator in kJ/kg\n",
+    "h_sup=422.5;# Enthalpy of superheated vapour leaving compressor in kJ/kg\n",
+    "\n",
+    "# Calculation\n",
+    "CarnotCOP=T_l/(T_h-T_l);\n",
+    "print\"The Carnot COP for the process is\",round(CarnotCOP,1)\n",
+    "# For Refrigeration cycle,\n",
+    "CarnotCOP=T_e/(T_c-T_e);\n",
+    "print\"The Carnot COP for the refrigeration cycle is\",round(CarnotCOP,1)\n",
+    "# For R134a,\n",
+    "Q=h_e-h_i;# Cooling effect in kJ/kg\n",
+    "W_in=h_sup-h_e;# Compressor energy input in kJ/kg\n",
+    "COP=Q/W_in;# Ideal R134a vapour compression cycle COP\n",
+    "print\"The Carnot COP for the ideal vapour compression cycle  is\",round(COP,1)\n",
+    "\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30.ipynb
new file mode 100644
index 00000000..475ed0a5
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30.ipynb
@@ -0,0 +1,72 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 30:Efficiency, Running Cost and Carbon Footprint"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 30.1,PAGE NUMBER:358"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "P=15;# kW\n",
+    "n_b=85;# The effiency of the gas boiler in %\n",
+    "SCOP=3;# An average or seasonal COP (SCOP) of heat pump\n",
+    "\n",
+    "# Calcualtion\n",
+    "# For the gas boiler\n",
+    "R_pf=17.65;# Rate of primary fuel use in kW\n",
+    "m_co2=0.19;# The mass of carbon in kg\n",
+    "R_co2=R_pf*m_co2;# Rate of CO_2 emission in kg/h\n",
+    "# For example\n",
+    "Gp=3;# p/kWh\n",
+    "Rc=R_pf*Gp;# Boiler Running cost in p per hour of heating\n",
+    "print\"Boiler Running cost=%2.0fp per hour of heating.\"%Rc\n",
+    "# For heat pump\n",
+    "T_R_pf=10;#  Rate of primary fuel use in kW (total)\n",
+    "R_pf=5;# Rate of primary fuel use in kW\n",
+    "m_co2=0.43;# The mass of carbon in kg\n",
+    "R_co2=R_co2=R_pf*m_co2;# Rate of CO_2 emission in kg/h\n",
+    "# For example\n",
+    "Ep=9;# p/kWh\n",
+    "Rc=R_pf*Ep;# HP Running cost in p per hour of heating\n",
+    "print\"HP Running cost=%2.0fp per hour of heating.\"%Rc"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30_SCStTvJ.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30_SCStTvJ.ipynb
new file mode 100644
index 00000000..475ed0a5
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER30_SCStTvJ.ipynb
@@ -0,0 +1,72 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 30:Efficiency, Running Cost and Carbon Footprint"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 30.1,PAGE NUMBER:358"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "P=15;# kW\n",
+    "n_b=85;# The effiency of the gas boiler in %\n",
+    "SCOP=3;# An average or seasonal COP (SCOP) of heat pump\n",
+    "\n",
+    "# Calcualtion\n",
+    "# For the gas boiler\n",
+    "R_pf=17.65;# Rate of primary fuel use in kW\n",
+    "m_co2=0.19;# The mass of carbon in kg\n",
+    "R_co2=R_pf*m_co2;# Rate of CO_2 emission in kg/h\n",
+    "# For example\n",
+    "Gp=3;# p/kWh\n",
+    "Rc=R_pf*Gp;# Boiler Running cost in p per hour of heating\n",
+    "print\"Boiler Running cost=%2.0fp per hour of heating.\"%Rc\n",
+    "# For heat pump\n",
+    "T_R_pf=10;#  Rate of primary fuel use in kW (total)\n",
+    "R_pf=5;# Rate of primary fuel use in kW\n",
+    "m_co2=0.43;# The mass of carbon in kg\n",
+    "R_co2=R_co2=R_pf*m_co2;# Rate of CO_2 emission in kg/h\n",
+    "# For example\n",
+    "Ep=9;# p/kWh\n",
+    "Rc=R_pf*Ep;# HP Running cost in p per hour of heating\n",
+    "print\"HP Running cost=%2.0fp per hour of heating.\"%Rc"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6.ipynb
new file mode 100644
index 00000000..b08708fb
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6.ipynb
@@ -0,0 +1,150 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 6:Condensers and Cooling Towers"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.1,PAGE NUMBER:77"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q_1=12;# Heat load in kW\n",
+    "T_c1=50;# The condensing temperature in °C\n",
+    "T_o1=35;# The maximum outdoor temperature in °C\n",
+    "T_o2=15;# The reduced outdoor temperature in °C\n",
+    "Q_2=8;# The reduced heat load in kW\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=T_c1-T_o1;# Temperature Difference in K\n",
+    "CR=Q_1*10**3/deltaT;# Condenser Rating in W/K\n",
+    "CR=CR*10**-3;# Condenser Rating in kW/K\n",
+    "deltaT_15=Q_2/CR;# Temperature Difference at 15°C \n",
+    "T_c2=T_o2+deltaT_15;#The Condensing temperature at 15°C\n",
+    "print\"Cooling Rating=\",round(CR,1),\"kW/K\"\n",
+    "print\"Temperature Difference at 15°C=%2.0f°C\"%deltaT_15\n",
+    "print\"The Condensing temperature at 15°C=%2.0f°C\"%T_c2"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.2,PAGE NUMBER:80"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "deltaT=5.2;# The temperature rise in K\n",
+    "E=930;# Total duty at the condenser in kW\n",
+    "C_pw=4.187;# The specific heat of water in kJ/kg K\n",
+    "\n",
+    "# Calculation\n",
+    "mdot=E/(deltaT*C_pw);# The amount of water required in kg/s\n",
+    "print round(mdot,0),\"kg/s water flow is required.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Example 6.3,PAGE NUMBER:80"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "E_t=880;# Total duty at the condenser in kW\n",
+    "E_wcp=15;# Total duty at water-circulating pump in kw\n",
+    "\n",
+    "# Calculation\n",
+    "E=E_t+E_wcp;# Total tower duty in kW\n",
+    "w_er=E*0.41*10**-3;# Evaporation rate in kg/s\n",
+    "Cr_80=30;# Circulation rate in kg/s\n",
+    "Cr_160=60;# Circulation rate in kg/s\n",
+    "w_air=E*0.06;# Air flow rate in kg/s\n",
+    "print\"\\nEvaporation rate=%0.2f kg/s \\nCirculation rate,80times=%2.0f kg/s \\nCirculation rate,160times=%2.0f kg/s \\nAir flow rate=%2.0f kg/s\"%(w_er,Cr_80,Cr_160,w_air)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.4,PAGE NUMBER:85"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Cc=700;# The cooling capacity in kW\n",
+    "P_c=170;# The compressor power in kW\n",
+    "c_b=0.0012;# Concentration of solids in bleed-off (kg/kg)\n",
+    "c_m=0.00056;# Concentration of solids in make-up water in kg/kg\n",
+    "\n",
+    "# Calculation\n",
+    "E_tc=Cc+P_c;# Cooling tower capacity in kW\n",
+    "h_fg=2420;# Latent heat of water vapour in kJ/kg\n",
+    "w_e=E_tc*10**3/h_fg;# Rate of evaporation in g/s\n",
+    "w_m=(w_e*(c_b))/(c_b-c_m);# Rate of make up in kg/s\n",
+    "w_bo=w_m-w_e;# Rate of bleed off in kg/s\n",
+    "print\"\\nRate of make up=%0.2f kg/s \\nRate of bleed off=%0.2f kg/s\"%(w_m/1000,w_bo/1000)\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6_r7ylWQR.ipynb b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6_r7ylWQR.ipynb
new file mode 100644
index 00000000..b08708fb
--- /dev/null
+++ b/Refrigeration_and_Air-Conditioning_by_G.F._Hundy,_A.A._Trott._and_le._Welch/CHAPTER6_r7ylWQR.ipynb
@@ -0,0 +1,150 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# CHAPTER 6:Condensers and Cooling Towers"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.1,PAGE NUMBER:77"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Q_1=12;# Heat load in kW\n",
+    "T_c1=50;# The condensing temperature in °C\n",
+    "T_o1=35;# The maximum outdoor temperature in °C\n",
+    "T_o2=15;# The reduced outdoor temperature in °C\n",
+    "Q_2=8;# The reduced heat load in kW\n",
+    "\n",
+    "# Calculation\n",
+    "deltaT=T_c1-T_o1;# Temperature Difference in K\n",
+    "CR=Q_1*10**3/deltaT;# Condenser Rating in W/K\n",
+    "CR=CR*10**-3;# Condenser Rating in kW/K\n",
+    "deltaT_15=Q_2/CR;# Temperature Difference at 15°C \n",
+    "T_c2=T_o2+deltaT_15;#The Condensing temperature at 15°C\n",
+    "print\"Cooling Rating=\",round(CR,1),\"kW/K\"\n",
+    "print\"Temperature Difference at 15°C=%2.0f°C\"%deltaT_15\n",
+    "print\"The Condensing temperature at 15°C=%2.0f°C\"%T_c2"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.2,PAGE NUMBER:80"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "deltaT=5.2;# The temperature rise in K\n",
+    "E=930;# Total duty at the condenser in kW\n",
+    "C_pw=4.187;# The specific heat of water in kJ/kg K\n",
+    "\n",
+    "# Calculation\n",
+    "mdot=E/(deltaT*C_pw);# The amount of water required in kg/s\n",
+    "print round(mdot,0),\"kg/s water flow is required.\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Example 6.3,PAGE NUMBER:80"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "E_t=880;# Total duty at the condenser in kW\n",
+    "E_wcp=15;# Total duty at water-circulating pump in kw\n",
+    "\n",
+    "# Calculation\n",
+    "E=E_t+E_wcp;# Total tower duty in kW\n",
+    "w_er=E*0.41*10**-3;# Evaporation rate in kg/s\n",
+    "Cr_80=30;# Circulation rate in kg/s\n",
+    "Cr_160=60;# Circulation rate in kg/s\n",
+    "w_air=E*0.06;# Air flow rate in kg/s\n",
+    "print\"\\nEvaporation rate=%0.2f kg/s \\nCirculation rate,80times=%2.0f kg/s \\nCirculation rate,160times=%2.0f kg/s \\nAir flow rate=%2.0f kg/s\"%(w_er,Cr_80,Cr_160,w_air)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6.4,PAGE NUMBER:85"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# Variable declaration\n",
+    "Cc=700;# The cooling capacity in kW\n",
+    "P_c=170;# The compressor power in kW\n",
+    "c_b=0.0012;# Concentration of solids in bleed-off (kg/kg)\n",
+    "c_m=0.00056;# Concentration of solids in make-up water in kg/kg\n",
+    "\n",
+    "# Calculation\n",
+    "E_tc=Cc+P_c;# Cooling tower capacity in kW\n",
+    "h_fg=2420;# Latent heat of water vapour in kJ/kg\n",
+    "w_e=E_tc*10**3/h_fg;# Rate of evaporation in g/s\n",
+    "w_m=(w_e*(c_b))/(c_b-c_m);# Rate of make up in kg/s\n",
+    "w_bo=w_m-w_e;# Rate of bleed off in kg/s\n",
+    "print\"\\nRate of make up=%0.2f kg/s \\nRate of bleed off=%0.2f kg/s\"%(w_m/1000,w_bo/1000)\n"
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/sample_notebooks/sai kiranmalepati/Sample_Notebook.ipynb b/sample_notebooks/sai kiranmalepati/Sample_Notebook.ipynb
new file mode 100644
index 00000000..03ccf753
--- /dev/null
+++ b/sample_notebooks/sai kiranmalepati/Sample_Notebook.ipynb
@@ -0,0 +1,349 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# SAMPLE NOTEBOOK"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "\n",
+    "\n",
+    "## ch-9 page 227   pb-1"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "('load current =', 21.78649237472767)\n",
+      "('design current=', 28.32244008714597)\n",
+      "('Derating factor=', 0.92)\n",
+      "('fuse rating=', 30.785260964289098)\n"
+     ]
+    }
+   ],
+   "source": [
+    "\n",
+    "from __future__ import division\n",
+    "\n",
+    "import math\n",
+    "\n",
+    "vi=120;\n",
+    "k=1000;\n",
+    "pi=2*k;\n",
+    "eff=0.90;\n",
+    "pf=0.85;\n",
+    "t=65;\n",
+    "\n",
+    "lc=(pi)/(vi*eff*pf);\n",
+    "print('load current =',lc);\n",
+    "\n",
+    "dc=1.3*lc;\n",
+    "print('design current=',dc);\n",
+    "\n",
+    "df=(0.2/100)*(t-25);\n",
+    "df=11.5*df;\n",
+    "print('Derating factor=',df);\n",
+    "\n",
+    "fr=dc/df;\n",
+    "print('fuse rating=',fr);\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "\n",
+    "\n",
+    "## ch-10 page 268   pb-6"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "('power delivered =', 500000.0, 'watts')\n",
+      "('power loss=', 10000.0, 'watts')\n",
+      "(510583.1892725521, 241709.44403085182)\n",
+      "('kvar_cap=', 268.87374524170025)\n",
+      "('c=', 10.111669570616154, 'micro farad/ph')\n",
+      "('differences in kva demand=', 158.7301587301588)\n",
+      "('loss in cable =', 0.6049382716049381)\n",
+      "('cost saving=', 5294.849999999999)\n",
+      "('total three phase capacitor cost=', 48397.274143506045, '$')\n",
+      "('capacitor cost will be recoverred in', 9.140442910281887, 'months')\n"
+     ]
+    }
+   ],
+   "source": [
+    "\n",
+    "from __future__ import division\n",
+    "\n",
+    "import math\n",
+    "\n",
+    "lpf1=0.70;\n",
+    "lpf2=0.90;\n",
+    "vi=460;\n",
+    "f=60;\n",
+    "k=1000;\n",
+    "p=1500*k;\n",
+    "time=300;\n",
+    "cost=60;\n",
+    "l=2/100;\n",
+    "theta1=45.6;\n",
+    "theta2=25.8;\n",
+    "pd=p/3; #since 3 phase;\n",
+    "pl=l*pd;\n",
+    "\n",
+    "print('power delivered =',pd,'watts');\n",
+    "print('power loss=',pl,'watts');\n",
+    "\n",
+    "var1=pd*(math.tan((math.pi/180)*theta1));\n",
+    "var2=pd*(math.tan((math.pi/180)*theta2));\n",
+    "var=var1-var2;\n",
+    "print(var1,var2);\n",
+    "kvar=var/1000;\n",
+    "print('kvar_cap=',kvar);\n",
+    "\n",
+    "vp=vi/(math.sqrt(3));\n",
+    "w=2*math.pi*f;\n",
+    "\n",
+    "c=(1000*kvar)/(w*vp*vp);\n",
+    "c=c*1000;\n",
+    "print('c=',c,'micro farad/ph');\n",
+    "\n",
+    "kva1=(pd/1000)/lpf1;\n",
+    "kva2=(pd/1000)/lpf2;\n",
+    "\n",
+    "dkva=kva1-kva2;\n",
+    "print('differences in kva demand=',dkva);\n",
+    "\n",
+    "loss=(lpf1/lpf2)*(lpf1/lpf2);\n",
+    "print('loss in cable =',loss);\n",
+    "\n",
+    "kvas=3*158.72;\n",
+    "\n",
+    "scl=3*3.95;\n",
+    "\n",
+    "tcost=10*kvas+0.15*scl*time;\n",
+    "print('cost saving=',tcost);\n",
+    "\n",
+    "tccost=cost*3*kvar;\n",
+    "\n",
+    "print('total three phase capacitor cost=',tccost,'$');\n",
+    "\n",
+    "duration=tccost/tcost;\n",
+    "print('capacitor cost will be recoverred in',duration,'months');\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "\n",
+    "\n",
+    "## ch-13 page 340   pb-3"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "('duty cycle=', 0.5)\n",
+      "('avg o/p voltage=', 60.0)\n",
+      "('avg o/p current=', 4.0)\n",
+      "('avg o/p power=', 240.0)\n",
+      "('L min=', 3.0, 'mhenry')\n"
+     ]
+    }
+   ],
+   "source": [
+    "\n",
+    "from __future__ import division\n",
+    "\n",
+    "import math\n",
+    "\n",
+    "v=120;\n",
+    "i=2;\n",
+    "f=1000;\n",
+    "to=(0.5)/1000;\n",
+    "\n",
+    "T=1/f;\n",
+    "\n",
+    "dr=(to)/T;\n",
+    "print('duty cycle=',dr);\n",
+    "\n",
+    "vo=dr*v;\n",
+    "io=i/dr;\n",
+    "po=vo*io;\n",
+    "\n",
+    "print('avg o/p voltage=',vo);\n",
+    "print('avg o/p current=',io);\n",
+    "print('avg o/p power=',po);\n",
+    "\n",
+    "L=(dr*(v/10))/2;\n",
+    "\n",
+    "print('L min=',L,'mhenry');\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "\n",
+    "\n",
+    "## ch-14 page 363   pb-4"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "('V dc=', 339.4112549695428)\n",
+      "('I dc=', 5.892556509887896)\n",
+      "('fundamental ac side rms current =', 8.333333333333334)\n",
+      "('THD=', 0.8259394650941436)\n",
+      "('I ac(rms)=', 10.77677544021814)\n",
+      "('I dc(rms)=', 9.023118455759443)\n"
+     ]
+    }
+   ],
+   "source": [
+    "\n",
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "v=240;\n",
+    "f=60;\n",
+    "p=2000;\n",
+    "dpf=1;\n",
+    "k1=73.2;k2=36.6;k3=8.1;k4=5.7;\n",
+    "k5=4.1;k6=2.9;k7=0.8;k8=0.4;\n",
+    "h1=3;h2=5;h3=7;h4=9;h5=11;h6=13;h7=17;\n",
+    "\n",
+    "vdc=math.sqrt(2)*v;\n",
+    "\n",
+    "idc=p/vdc;\n",
+    "print('V dc=',vdc);\n",
+    "print('I dc=',idc);\n",
+    "pac=p/dpf;\n",
+    "\n",
+    "\n",
+    "is1=p/v;\n",
+    "\n",
+    "print('fundamental ac side rms current =',is1);\n",
+    "\n",
+    "k=(k1*k1)+k2*k2+k3*k3+k4*k4+k5*k5+k6*k6+k7*k7;\n",
+    "thd=(math.sqrt(k))/100;\n",
+    "print('THD=',thd);\n",
+    "\n",
+    "iac=is1*(math.sqrt(1+(0.82*0.82)));\n",
+    "\n",
+    "idcr=math.sqrt((iac*iac)-(idc*idc));\n",
+    "\n",
+    "print('I ac(rms)=',iac);\n",
+    "print('I dc(rms)=',idcr);\n",
+    "\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "\n",
+    "\n",
+    "## ch-16 page 454   pb-6"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "('fundamental load current =', 240.5626121623441)\n"
+     ]
+    }
+   ],
+   "source": [
+    "\n",
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "v=480;\n",
+    "k=1000;\n",
+    "p=200*k;\n",
+    "thd=600;\n",
+    "\n",
+    "lc=p/(math.sqrt(3)*v);\n",
+    "\n",
+    "print('fundamental load current =',lc);\n"
+   ]
+  }
+ ],
+ "metadata": {
+  "anaconda-cloud": {},
+  "kernelspec": {
+   "display_name": "Python [default]",
+   "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": "2.7.12"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}