{ "metadata": { "name": "", "signature": "sha256:f4925d0b2e463188ddde753ce40d3c66c53a733743431193f8411c4532c3afc1" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter8-Geothermal Energy" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.5.1-pg 450" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Ex8.5.1.;calculate: steam flow rate,cooling water flow,plant efficiency,Heat rate\n", "\n", "##Enthalpy at point 1 at (31 kg/cm^2)=669.6 kcal/kg\n", "##H1=H2=H3,enthalpy remain constant during throttling\n", "H1=669.7;##unit= kcal/kg\n", "H2=669.7;##unit= kcal/kg\n", "H3=669.7;##unit= kcal/kg\n", "##At point 3,\n", "P3=9.55;##unit= kg/cm^2\n", "##specific volume\n", "vs3=0.22;##unit=m^3/kg\n", "##Entropy\n", "S3=1.580\n", "T3=190.;##unit=degree C,(degree of superheat=13 degree C)\n", "##S4_s at 0.34 kg/cm^2=S3\n", "##x4_s=0.838\n", "##and H4_s=hs+xL\n", "H4_s=72.+(0.838*556)\n", "print'%s %.2f %s'%(\" H4_s=\",H4_s,\" kcal/kg\")\n", "##Isentropic turbine work=H3-H4_s\n", "ITW=H3-H4_s;\n", "print'%s %.2f %s'%(\"\\n Isentropic turbine work=\",ITW,\" kcal/kg\");\n", "##Actual turbine work\n", "ATW=0.80*ITW;\n", "print'%s %.2f %s'%(\"\\n Actual turbine work=\",ATW,\" kcal/kg\");\n", "H4=669.7-ATW;\n", "print'%s %.2f %s'%(\"\\n H4=\",H4,\" kcal/kg\")\n", "h5_6=72;##unit= kcal/kg; (Ignoring pump work)\n", "##sensible heat h7=h5=25 kcal/kg\n", "h5=25;##unit=kcal/kg\n", "h7=25;##unit=kcal/kg\n", "##Turbine steam flow\n", "TSF=(250*0.860*10**6)/(ATW*0.9);\n", "print'%s %.2f %s'%(\"\\n Turbine steam flow=\",TSF,\" kg/hr\");\n", "##let\n", "m4=TSF;\n", "##Turbine volume flow\n", "TVF=(TSF/60)*vs3;\n", "print'%s %.2f %s'%(\"\\n Turbine volume flow=\",TVF,\" m^3/min\");\n", "##cooling water flow m7:m7(h5_6-h7)=m4(H4-h5_6)\n", "m7=((H4-h5_6)/(h5_6-h7))*m4;\n", "print'%s %.2f %s'%(\"\\n cooling water flow m7=\",m7,\" kg/hr\");\n", "Heat_added=H1-h5_6;\n", "print'%s %.2f %s'%(\"\\n Heat_added=\",Heat_added,\" kcal/kg\");\n", "##plant efficiency=(Actual Turbine work*nmg)/Heat added\n", "##nmg=combined mechanical and electrical efficiency of turbine-generator\n", "nmg=0.90;\n", "Plant_efficiency=(ATW*nmg)/Heat_added;\n", "plant_efficiency=Plant_efficiency*100.;\n", "print'%s %.2f %s'%(\"\\n Plant Efficiency nplant=\",plant_efficiency,\" persent\");\n", "##Plant heat rate=(860*Heat_added)/net_work\n", "##net_work=105.36*0.90\n", "Plant_heat_rate=(860./Plant_efficiency);\n", "print'%s %.2f %s'%(\"\\n Plant heat rate=\",Plant_heat_rate,\" kcal/kWH\");\n", "\n", "\n", "##The value of \"turbine steam flow\" is wrong due to calculating mistak in textbook,due to which the further value related with it is given wrong\n", "##The values are corrected in this program\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " H4_s= 537.93 kcal/kg\n", "\n", " Isentropic turbine work= 131.77 kcal/kg\n", "\n", " Actual turbine work= 105.42 kcal/kg\n", "\n", " H4= 564.28 kcal/kg\n", "\n", " Turbine steam flow= 2266119.59 kg/hr\n", "\n", " Turbine volume flow= 8309.11 m^3/min\n", "\n", " cooling water flow m7= 23735548.77 kg/hr\n", "\n", " Heat_added= 597.70 kcal/kg\n", "\n", " Plant Efficiency nplant= 15.87 persent\n", "\n", " Plant heat rate= 5417.84 kcal/kWH\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8.5.2-pg460" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Ex8.5.2.;calculate: hot water flow,condenser cooling water flow,cycle efficiency,plant heat rate.\n", "import math\n", "H1=669.6;##unit=kcal/kg\n", "H2=669.6;##unit=kcal/kg\n", "##pressure at point 2,is 10.5 kg/cm^2;thus,\n", "T2=195.;##unit=degree celcius; (14 degree celcius of superheat)\n", "s2=1.567;\n", "vsup=0.27;\n", "x3s=0.832;\n", "H3s=535.;##unit=kcal/kg\n", "##Isentropic turbine work\n", "ITW=H2-H3s;\n", "print'%s %.2f %s'%(\" Isentropic turbine work=\",ITW,\" kcal/kg\");\n", "##Actual turbine work\n", "ATW=0.65*ITW;\n", "print'%s %.2f %s'%(\"\\n Actual turbine work=\",ATW,\" kcal/kg\");\n", "H3=669.6-ATW;\n", "print'%s %.2f %s'%(\"\\n H3=\",H3,\" kcal/kg\")\n", "##h_4-5(ignore bpump work)\n", "h4=72.4;##unit=kcal/kg\n", "##h6 at 27 degree c\n", "h6=27;##unit=kcal/kg\n", "##Turbine steam flow or hot water flow=power output/actual turbine work\n", "TSF=(10*10**6*0.86)/ATW;\n", "print'%s %.2f %s'%(\"\\n Turbine steam flow or hot water flow=\",TSF,\" kg/hr\");\n", "##consider cooling water flow m4:m3*(H3-h4)=m4(h4-h6)\n", "##or\n", "m4=((582.11-72.4)*0.983*10**5)/(72.4-27);\n", "print'%s %.2f %s'%(\"\\n cooling water flow=\",m4,\" kg/hr\");\n", "Heat_added=H1-h4\n", "print'%s %.2f %s'%(\"\\n Heat_added=\",Heat_added,\" kcal/kg\");\n", "##plant efficiency=Turbine work/Heat added\n", "Plant_efficiency=(ATW/Heat_added);\n", "plant_efficiency=Plant_efficiency*100;\n", "print'%s %.2f %s'%(\"\\n Plant Efficiency=\",plant_efficiency,\" persent\");\n", "##Plant heat rate=860/Plant Efficiency\n", "Plant_heat_rate=860./Plant_efficiency;\n", "print'%s %.2f %s'%(\"\\n Plant heat rate=\",Plant_heat_rate,\" kcal/kWh\");\n", "\n", "\n", "##The value of m3=14.03*10^5 is given wrong in the text book;the actual value is m3=11.03*10^5\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Isentropic turbine work= 134.60 kcal/kg\n", "\n", " Actual turbine work= 87.49 kcal/kg\n", "\n", " H3= 582.11 kcal/kg\n", "\n", " Turbine steam flow or hot water flow= 98296.95 kg/hr\n", "\n", " cooling water flow= 1103623.19 kg/hr\n", "\n", " Heat_added= 597.20 kcal/kg\n", "\n", " Plant Efficiency= 14.65 persent\n", "\n", " Plant heat rate= 5870.29 kcal/kWh\n" ] } ], "prompt_number": 2 } ], "metadata": {} } ] }