From 92cca121f959c6616e3da431c1e2d23c4fa5e886 Mon Sep 17 00:00:00 2001 From: hardythe1 Date: Tue, 7 Apr 2015 15:58:05 +0530 Subject: added books --- .../Chapter11.ipynb | 353 +++++++++++++++++++++ 1 file changed, 353 insertions(+) create mode 100755 Thermodynamics_An_Engineering_Approach/Chapter11.ipynb (limited to 'Thermodynamics_An_Engineering_Approach/Chapter11.ipynb') diff --git a/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb b/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb new file mode 100755 index 00000000..460e3a17 --- /dev/null +++ b/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb @@ -0,0 +1,353 @@ +{ + "metadata": { + "name": "" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 11: Refrigeration Cycles" + ] + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-1 ,Page No.613" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given values\n", + "P1=0.14;#intial pressure in MPa\n", + "P2=0.8;#final pressure in MPa\n", + "m=0.05;#mass flow rate in kg/s\n", + "\n", + "#from refrigerant-134a tables\n", + "h1=239.16;\n", + "s1=0.94456;\n", + "h2=275.39;\n", + "h3=95.47;\n", + "\n", + "#calculation\n", + "s2=s1;#isentropic process \n", + "h4=h3;#throttling\n", + "QL=(h1-h4)*m;\n", + "Wm=m*(h2-h1);\n", + "Qh=m*(h2-h3);\n", + "COPR=QL/Wm;\n", + "print'the rate of heat removal from the refrigerated space %f kW'%round(QL,2);\n", + "print'the power input to the compressor %f kW'%round(Wm,2);\n", + "print'the rate of heat rejection to the environment %f kW'%round(Qh);\n", + "print'the COP of the refrigerator is %f'%round(COPR,2);" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the rate of heat removal from the refrigerated space 7.180000 kW\n", + "the power input to the compressor 1.810000 kW\n", + "the rate of heat rejection to the environment 9.000000 kW\n", + "the COP of the refrigerator is 3.970000\n" + ] + } + ], + "prompt_number": 3 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-2 ,Page No.615" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given data\n", + "m=0.05;#mass flow rate in kg/s\n", + "P1=0.14;#inlet pressure in MPa\n", + "T1=-10;#inlet temperature in C\n", + "P2=0.8;#outlet pressure in MPa\n", + "T2=50;#outlet temperature in C\n", + "P3=0.72;#condensor pressure in MPa\n", + "T3=26;#condensor temperature in C\n", + "\n", + "#from refrigerant tables\n", + "h1=246.36;\n", + "h2=286.69;\n", + "h3=87.83;\n", + "h2S=284.21;#at isentropic conditions\n", + "\n", + "#calculations\n", + "h4=h3;#throttling\n", + "QL=m*(h1-h4);\n", + "Wm=m*(h2-h1);\n", + "nC=(h2S-h1)/(h2-h1);\n", + "COPR=QL/Wm;\n", + "print'the rate of heat removal from the refrigerated space %f kW'%round(QL,2);\n", + "print'the power input to the compressor %f kW'%round(Wm,2);\n", + "print'the isentropic efficiency of the compressor is %f'%round(nC,3);\n", + "print'the COP of the refrigerator is %f'%round(COPR,2);" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the rate of heat removal from the refrigerated space 7.930000 kW\n", + "the power input to the compressor 2.020000 kW\n", + "the isentropic efficiency of the compressor is 0.939000\n", + "the COP of the refrigerator is 3.930000\n" + ] + } + ], + "prompt_number": 5 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-3 ,Page No.621" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given data\n", + "mA=0.05;#mass flow rate in kg/s\n", + "P1=0.14;#inlet pressure in MPa\n", + "P5=0.32;#pressure at heat exchanger in MPa\n", + "P7=0.8;#oultet pressure in MPa\n", + "\n", + "#from tables\n", + "h1=239.16;\n", + "h2=255.93;\n", + "h3=55.16;\n", + "h5=251.88;\n", + "h6=270.92;\n", + "h7=95.47;\n", + "\n", + "#calculations\n", + "h4=h3;#throttling\n", + "h8=h7;#throttling\n", + "# E out = E in\n", + "# mA*h5 + mB*h3 = mA*h8 + mB*h2\n", + "mB=mA*(h5-h8)/(h2-h3);\n", + "QL=mB*(h1-h4);\n", + "# W in = Wcomp I,in + Wcomp II,in\n", + "Win=mA*(h6-h5)+mB*(h2-h1);\n", + "COPR=QL/Win;\n", + "print'the mass flow rate of the refrigerant through the lower cycle %f kg/s'%round(mB,4);\n", + "print'the rate of heat removal from the refrigerated space %f kW'%round(QL,2);\n", + "print'the power input to the compressor %f kW'%round(Win,2);\n", + "print'the coefficient of performance of this cascade refrigerator is %f'%round(COPR,2);\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the mass flow rate of the refrigerant through the lower cycle 0.039000 kg/s\n", + "the rate of heat removal from the refrigerated space 7.170000 kW\n", + "the power input to the compressor 1.610000 kW\n", + "the coefficient of performance of this cascade refrigerator is 4.460000\n" + ] + } + ], + "prompt_number": 8 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-4 ,Page No.624" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given data\n", + "P1=0.14;#inlet pressure in MPa\n", + "P5=0.32;#throttled pressure in MPa\n", + "P7=0.8;#oultet pressure in MPa\n", + "\n", + "#from tables\n", + "h1=239.16;\n", + "h2=255.93;\n", + "h3=251.88;\n", + "h5=95.47;\n", + "h7=55.16;\n", + "\n", + "#from saturated liquid-vapour table\n", + "#at P=0.32 MPa\n", + "hf=55.16;\n", + "hfg=196.71;\n", + "\n", + "#calculations\n", + "h8=h7;#throttling\n", + "h6=h5;#throttling\n", + "#the quality at state 6\n", + "x6=(h6-hf)/hfg;\n", + "qL=(1-x6)*(h1-h8);\n", + "# W in = Wcomp I,in + Wcomp II,in\n", + "#enthalaoy at state 9\n", + "# E out = E in\n", + "h9=x6*h3+(1-x6)*h2;\n", + "# s9 = s4 i.e isentropic process\n", + "#at 0.8MPa and s4=0.9416 kJ/kg\n", + "h4=274.48;\n", + "Win=(1-x6)*(h2-h1)+(1)*(h4-h9);\n", + "COPR=qL/Win;\n", + "print'the fraction of the refrigerant that evaporates as it is throttled to the flash chamber is %f'%round(x6,4);\n", + "print'the amount of heat removed from the refrigerated space %f kJ/kg'%round(qL,1);\n", + "print'the compressor work per unit mass of refrigerant flowing through the condensor %f kJ/kg'%round(Win,2);\n", + "print'the coefficient of performance is %f'%round(COPR,2)\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the fraction of the refrigerant that evaporates as it is throttled to the flash chamber is 0.204900\n", + "the amount of heat removed from the refrigerated space 146.300000 kJ/kg\n", + "the compressor work per unit mass of refrigerant flowing through the condensor 32.710000 kJ/kg\n", + "the coefficient of performance is 4.470000\n" + ] + } + ], + "prompt_number": 10 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-5 ,Page No.630" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given data\n", + "m=0.1;#mass flow rate in lbm/s\n", + "T1=0+460;#refigerated space at temperature in R\n", + "T3=80+460;#temperature of surrounding medium in R\n", + "\n", + "#from Table A\u201317E\n", + "# at T1\n", + "h1=109.90;\n", + "Pr1=.7913;\n", + "#pressure ratio at compressor is 4\n", + "Pr2=4*Pr1;\n", + "#at Pr2\n", + "h2=163.5;\n", + "T2=683;\n", + "#at T3\n", + "h3=129.06;\n", + "Pr3=1.3860;\n", + "#pressure ratio at compressor is 4\n", + "Pr4=Pr3/4;\n", + "#at Pr4\n", + "h4=86.7;\n", + "T4=363;\n", + "\n", + "#calculations\n", + "qL=h1-h4;\n", + "Wout=h3-h4;\n", + "Win=h2-h1;\n", + "COPR=qL/(Win-Wout);\n", + "Qrefrig=m*qL;\n", + "print'the minimum temperatures in the cycle %f F'%round(T4-460);\n", + "print'the maximum temperatures in the cycle %f F'%round(T2-460);\n", + "print'the coefficient of performance is %f'%round(COPR,2)\n", + "print'the rate of refrigeration for a mass flow rate of 0.1 lbm/s. %f Btu/s'%round(Qrefrig,2)" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the minimum temperatures in the cycle -97.000000 F\n", + "the maximum temperatures in the cycle 223.000000 F\n", + "the coefficient of performance is 2.060000\n", + "the rate of refrigeration for a mass flow rate of 0.1 lbm/s. 2.320000 Btu/s\n" + ] + } + ], + "prompt_number": 13 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 11-6 ,Page No.636" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#given data\n", + "COPR=0.1;#refrigerator COP\n", + "T1=20;#intial temp in C\n", + "T2=4;#final temp in C\n", + "t=30*60;#total time required in sec\n", + "V=0.350;#volumne of can in L\n", + "\n", + "#constants used\n", + "p=1;#on kg/L\n", + "c=4.18;#in kJ/kg-C from Table A-3\n", + "\n", + "#calculations\n", + "m=p*V;\n", + "Qcooling=m*c*(T1-T2)/t*1000;#converted in W by multiplying by 1000\n", + "Win=Qcooling/COPR;\n", + "print'the average electric power consumed by the thermoelectric refrigerator %i W'%round(Win)" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the average electric power consumed by the thermoelectric refrigerator 130 W\n" + ] + } + ], + "prompt_number": 14 + } + ], + "metadata": {} + } + ] +} \ No newline at end of file -- cgit