diff options
Diffstat (limited to 'Thermodynamics_An_Engineering_Approach/Chapter11.ipynb')
| -rwxr-xr-x | Thermodynamics_An_Engineering_Approach/Chapter11.ipynb | 353 |
1 files changed, 0 insertions, 353 deletions
diff --git a/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb b/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb deleted file mode 100755 index 460e3a17..00000000 --- a/Thermodynamics_An_Engineering_Approach/Chapter11.ipynb +++ /dev/null @@ -1,353 +0,0 @@ -{
- "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 |