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diff --git a/Basic_And_Applied_Thermodynamics_by_P._K._Nag/Chapter12.ipynb b/Basic_And_Applied_Thermodynamics_by_P._K._Nag/Chapter12.ipynb index 06d1811b..540dfc4d 100755..100644 --- a/Basic_And_Applied_Thermodynamics_by_P._K._Nag/Chapter12.ipynb +++ b/Basic_And_Applied_Thermodynamics_by_P._K._Nag/Chapter12.ipynb @@ -1,887 +1,890 @@ -{
- "metadata": {
- "name": "",
- "signature": "sha256:b39ef4709eada52e4edea3c455c191cc976086e523f6bfbc880f8c46ec08b27a"
- },
- "nbformat": 3,
- "nbformat_minor": 0,
- "worksheets": [
- {
- "cells": [
- {
- "cell_type": "heading",
- "level": 1,
- "metadata": {},
- "source": [
- "Chapter 12: Vapour power cycle"
- ]
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.1:pg-492"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "# Part (a)\n",
- "P1 = 1 # Initial pressure in bar\n",
- "P2 = 10 # Final pressure in bar\n",
- "vf = 0.001043 # specific volume of liquid in m**3/kg\n",
- "Wrev = vf*(P1-P2)*1e5 # Work done\n",
- "\n",
- "print \"\\n Example 12.1\"\n",
- "print \"\\n The work required in saturated liquid form is \",Wrev/1000 ,\" kJ/kg\"\n",
- "#The answers vary due to round off error\n",
- "\n",
- "# Part (b)\n",
- "h1 = 2675.5 # Enthalpy at state 1 in kJ/kg\n",
- "s1 = 7.3594 # Entropy at state 1 kJ/kgK\n",
- "s2 = s1 # Isentropic process\n",
- "h2 = 3195.5 # Enthalpy at state 2 kJ/kg\n",
- "Wrev1 = h1-h2 # Work done\n",
- "print \"\\n The work required in saturated vapor form is \",Wrev1 ,\" kJ/kg\"\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.1\n",
- "\n",
- " The work required in saturated liquid form is -0.9387 kJ/kg\n",
- "\n",
- " The work required in saturated vapor form is -520.0 kJ/kg\n"
- ]
- }
- ],
- "prompt_number": 1
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.2:pg-493"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "h1 = 3159.3 # Enthalpy at state 1 in kJ/kg\n",
- "s1 = 6.9917 # Entropy at state 1 in kJ/kgK\n",
- "h3 = 173.88 # Enthalpy at state 3 in kJ/kg\n",
- "s3 = 0.5926 # Entropy at state 3 in kJ/kgK\n",
- "sfp2 = s3 # Isentropic process\n",
- "hfp2 = h3 # Isenthalpic process\n",
- "hfgp2 = 2403.1 # Latent heat of vaporization in kJ/kg\n",
- "sgp2 = 8.2287 # Entropy of gas in kJ/kgK\n",
- "vfp2 = 0.001008 # Specific volume in m**3/kg\n",
- "sfgp2 = 7.6361# Entropy of liquid in kJ/kgK\n",
- "x2s = (s1-sfp2)/(sfgp2)# Steam quality\n",
- "h2s = hfp2+(x2s*hfgp2) # Enthalpy at state 2s\n",
- "# Part (a)\n",
- "P1 = 20 # Turbine inlet pressure in bar\n",
- "P2 = 0.08 # Turbine exit pressure in bar\n",
- "h4s = vfp2*(P1-P2)*1e2+h3 # Enthalpy at state 4s\n",
- "Wp = h4s-h3 # Pump work\n",
- "Wt = h1-h2s # Turbine work\n",
- "Wnet = Wt-Wp # Net work \n",
- "Q1 = h1-h4s # Heat addition\n",
- "n_cycle = Wnet/Q1# Cycle efficiency\n",
- "print \"\\n Example 12.2\"\n",
- "print \"\\n Net work per kg of steam is \",Wnet ,\" kJ/kg\"\n",
- "#The answer provided in the textbook is wrong\n",
- "\n",
- "print \"\\n Cycle efficiency is \",n_cycle*100 ,\" percent\"\n",
- "\n",
- "# Part (b)\n",
- "n_p = 0.8 # pump efficiency\n",
- "n_t = 0.8# Turbine efficiency\n",
- "Wp_ = Wp/n_p # Pump work\n",
- "Wt_ = Wt*n_t # Turbine work\n",
- "Wnet_ = Wt_-Wp_# Net work\n",
- "P = 100*((Wnet-Wnet_)/Wnet) # Percentage reduction in net work\n",
- "n_cycle_ = Wnet_/Q1 # cycle efficiency\n",
- "P_ = 100*((n_cycle-n_cycle_)/n_cycle) #reduction in cycle\n",
- "print \"\\n\\n Percentage reduction in net work per kg of steam is \",P ,\" percent\"\n",
- "print \"\\n Percentage reduction in cycle efficiency is \",P_ ,\" percent\"\n",
- "\n",
- "#The answers vary due to round off error\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.2\n",
- "\n",
- " Net work per kg of steam is 969.599095338 kJ/kg\n",
- "\n",
- " Cycle efficiency is 32.4996706636 percent\n",
- "\n",
- "\n",
- " Percentage reduction in net work per kg of steam is 20.093190186 percent\n",
- "\n",
- " Percentage reduction in cycle efficiency is 20.093190186 percent\n"
- ]
- }
- ],
- "prompt_number": 2
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.3:pg-495"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "P1 = 0.08 # Exhaust pressure in bar\n",
- "sf = 0.5926 # Entropy of fluid in kJ/kgK\n",
- "x2s = 0.85 # Steam quality\n",
- "sg = 8.2287 # Entropy of gas in kJ/kgK\n",
- "s2s = sf+(x2s*(sg-sf)) # Entropy of mixture at state 2s in kJ/kgK\n",
- "s1 = s2s # Isentropic process\n",
- "P2 = 16.832 # by steam table opposite to s1 in bar\n",
- "h1 = 3165.54 # Enthalpy at state 1 in kJ/kg\n",
- "h2s = 173.88 + (0.85*2403.1) # Enthalpy at state 2s in kJ/kg\n",
- "h3 = 173.88# Enthalpy at state 3 in kJ/kg\n",
- "vfp2 = 0.001 # specific volume of liquid in m**3/kg\n",
- "h4s = h3 + (vfp2*(P2-P1)*100)# Enthalpy at state 4s in kJ/kg\n",
- "Q1 = h1-h4s # Heat addition\n",
- "Wt = h1-h2s # Turbine work\n",
- "Wp = h4s-h3 # Pump work\n",
- "n_cycle = 100*((Wt-Wp)/Q1) # Cycle efficiency\n",
- "Tm = (h1-h4s)/(s2s-sf) # Mean temperature of heat addition\n",
- "\n",
- "print \"\\n Example 12.3\"\n",
- "print \"\\n The greatest allowable steam pressure at the turbine inlet is \",P2 ,\" bar\"\n",
- "\n",
- "print \"\\n Rankine cycle efficiency is \",n_cycle ,\" percent\"\n",
- "\n",
- "print \"\\n Mean temperature of heat addition is \",Tm-273 ,\" degree celcius\"\n",
- "#The answers vary due to round off error\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.3\n",
- "\n",
- " The greatest allowable steam pressure at the turbine inlet is 16.832 bar\n",
- "\n",
- " Rankine cycle efficiency is 31.684100869 percent\n",
- "\n",
- " Mean temperature of heat addition is 187.657819629 degree celcius\n"
- ]
- }
- ],
- "prompt_number": 3
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.4:pg-496"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "h1 = 3465 # Enthalpy at state 1 in kJ/kgK\n",
- "h2s = 3065 #Enthalpy at state 2s in kJ/kgK \n",
- "h3 = 3565 #Enthalpy at state 3 in kJ/kgK\n",
- "h4s = 2300 # Enthalpy at state 4s in kJ/kgK\n",
- "x4s = 0.88 # Steam quality at state 4s\n",
- "h5 = 191.83# Enthalpy at state 5 in kJ/kgK\n",
- "v = 0.001 # specific volume in m**3/kg\n",
- "P = 150 # Boiler outlet pressure in bar\n",
- "Wp = v*P*100 # Pump work\n",
- "h6s = 206.83 # Enthalpy at state 6s in kJ/kgK\n",
- "Q1 = (h1-h6s)+(h3-h2s) # Heat addition\n",
- "Wt = (h1-h2s)+(h3-h4s) # Turbine work\n",
- "Wnet = Wt-Wp # Net work\n",
- "n_cycle = 100*Wnet/Q1 # cycle efficiency\n",
- "sr = 3600/Wnet #Steam rate\n",
- "\n",
- "print \"\\n Example 12.4 \\n\"\n",
- "print \"\\n Quality at turbine exhaust is \",0.88\n",
- "print \"\\n Cycle efficiency is \",n_cycle ,\" percent\"\n",
- "print \"\\n Steam rate is \",sr ,\" kg/kW h\"\n",
- "#The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.4 \n",
- "\n",
- "\n",
- " Quality at turbine exhaust is 0.88\n",
- "\n",
- " Cycle efficiency is 43.9043470625 percent\n",
- "\n",
- " Steam rate is 2.18181818182 kg/kW h\n"
- ]
- }
- ],
- "prompt_number": 4
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.5:pg-497"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "h1 = 3230.9 # Enthalpy at state 1 in kJ/kg\n",
- "s1 = 6.9212 # Entropy at state 1 in kJ/kgK\n",
- "s2 = s1 # Isentropic process\n",
- "s3 = s1 # Isentropic process\n",
- "h2 = 2796 # Enthalpy at state 2 in kJ/kg\n",
- "sf = 0.6493 # ENtropy of fluid onkJ/kgK\n",
- "sfg = 7.5009 # Entropy change due to vaporization\n",
- "x3 = (s3-sf)/sfg # steam quality\n",
- "h3 = 191.83 + x3*2392.8 # Enthalpy at state 3\n",
- "h4 = 191.83 # Enthalpy at state 4 in kJ/kg\n",
- "h5 = h4 # Isenthalpic process\n",
- "h6 = 640.23 # Enthalpy at state 6 in kJ/kg\n",
- "h7 = h6 # Isenthalpic process\n",
- "m = (h6-h5)/(h2-h5) # regenerative mass\n",
- "Wt = (h1-h2)+(1-m)*(h2-h3) # turbine work\n",
- "Q1 = h1-h6 # Heat addition\n",
- "n_cycle = 100*Wt/Q1 # Cycle efficiency\n",
- "sr = 3600/Wt # Steam rate\n",
- "s7 = 1.8607 # Entropy at state 7 in kJ/kgK\n",
- "s4 = 0.6493 # Entropy at state 4 in kJ/kgK \n",
- "Tm = (h1-h7)/(s1-s7) # Mean temperature of heat addition with regeneration\n",
- "Tm1 = (h1-h4)/(s1-s4) # Mean temperature of heat addition without regeneration\n",
- "dT = Tm-Tm1 # Change in temperature\n",
- "Wt_ = h1-h3 # Turbine work\n",
- "sr_ = 3600/Wt_ # Steam rate\n",
- "dsr = sr-sr_# Change in steam rate\n",
- "n_cycle_ = 100*(h1-h3)/(h1-h4) # Cycle effciency\n",
- "dn = n_cycle-n_cycle_# Change in efficiency\n",
- "print \"\\n Example 12.5\\n\"\n",
- "print \"\\n Efficiency of the cycle is \",n_cycle ,\" percent\"\n",
- "\n",
- "print \"\\n Steam rate of the cycle is \",sr ,\" kg/kW h\"\n",
- "#The answer provided in the textbook is wrong\n",
- "\n",
- "print \"\\n Increase in temperature due to regeneration is \",dT ,\" degree centigrade\"\n",
- "print \"\\n Increase in steam rate due to regeneration is \",dsr ,\" kg/kW h\"\n",
- "#The answer provided in the textbook is wrong\n",
- "\n",
- "print \"\\n Increase in Efficiency of the cycle due to regeneration is \",dn ,\" percent\"\n",
- "\n",
- "#The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.5\n",
- "\n",
- "\n",
- " Efficiency of the cycle is 36.0687573387 percent\n",
- "\n",
- " Steam rate of the cycle is 3.85264705574 kg/kW h\n",
- "\n",
- " Increase in temperature due to regeneration is 27.3862065182 degree centigrade\n",
- "\n",
- " Increase in steam rate due to regeneration is 0.385518227773 kg/kW h\n",
- "\n",
- " Increase in Efficiency of the cycle due to regeneration is 1.90293971596 percent\n"
- ]
- }
- ],
- "prompt_number": 5
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.6:pg-499"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "h1 = 3023.5 # Enthalpy of steam at state 1 in kJ/kg\n",
- "s1 = 6.7664 # Enthalpy of steam at state 1 in kJ/kgK\n",
- "s2 = s1 # Isentropic process\n",
- "s3 = s1 #Isentropic process\n",
- "s4 = s1 #Isentropic process\n",
- "t_sat_20 = 212 # Saturation temperature at 20 bar in degree Celsius\n",
- "t_sat_1 = 46 # Saturation temperature at 1 bar in degree Celsius\n",
- "dt = t_sat_20-t_sat_1 # Change in temperature\n",
- "n =3 # number of heaters\n",
- "t = dt/n # temperature rise per heater\n",
- "t1 = t_sat_20-t # Operational temperature of first heater\n",
- "t2 = t1-t# Operational temperature of second heater\n",
- "# 0.1 bar\n",
- "hf = 191.83 # Enthalpy of fluid in kJ/kg\n",
- "hfg = 2392.8 # Latent heat of vaporization in kJ/kg\n",
- "sf = 0.6493# Entropy of fluid in kJ/kgK\n",
- "sg = 8.1502# Entropy of gas in kJ/kgK\n",
- "# At 100 degree\n",
- "hf100 = 419.04 # Enthalpy of fluid in kJ/kg \n",
- "hfg100 = 2257.0# Latent heat of vaporization in kJ/kg \n",
- "sf100 = 1.3069 # Entropy of fluid in kJ/kgK \n",
- "sg100 = 7.3549 # Entropy of gas in kJ/kgK\n",
- "# At 150 degree\n",
- "hf150 = 632.20 # Enthalpy of fluid in kJ/kg \n",
- "hfg150 = 2114.3# Latent heat of vaporization in kJ/kg \n",
- "sf150 = 1.8418 # Entropy of fluid in kJ/kgK \n",
- "sg150 = 6.8379# Entropy of gas in kJ/kgK\n",
- "x2 = (s1-sf150)/4.9961 # Steam quality\n",
- "h2 = hf150+(x2*hfg150) # Enthalpy at state 2 in kJ/kg\n",
- "x3 = (s1-sf100)/6.0480 # Steam quality\n",
- "h3 = hf100+(x3*hfg100) # Enthalpy at state 3 in kJ/kg \n",
- "x4 = (s1-sf)/7.5010 # Steam quality\n",
- "h4 = hf+(x4*hfg)#Enthalpy at state 4 in kJ/kg\n",
- "h5 = hf # Enthalpy at state 5 in kJ/kg\n",
- "h6 = h5 #Enthalpy at state 6 in kJ/kg\n",
- "h7 = hf100 # Enthalpy at state 7 in kJ/kg\n",
- "h8 = h7 # Enthalpy at state 8 in kJ/kg\n",
- "h9 = 632.2 # Enthalpy at state 9 in kJ/kg\n",
- "h10 = h9 # Enthalpy at state 10 in kJ/kg\n",
- "m1 = (h9-h7)/(h2-h7) # regenerative mass \n",
- "m2 = ((1-m1)*(h7-h6))/(h3-h6) # regenerative mass\n",
- "Wt = 1*(h1-h2)+(1-m1)*(h2-h3)+(1-m1-m2)*(h3-h4) # Turbine work\n",
- "Q1 = h1-h9 # Heat addition\n",
- "Wp = 0 # Pump work is neglected\n",
- "n_cycle = 100*(Wt-Wp)/Q1 # Cycle efficiency\n",
- "sr = 3600/(Wt-Wp) # Steam rate\n",
- "\n",
- "print \"\\n Example 12.6\\n\"\n",
- "print \"\\n Steam quality at turbine exhaust is \",x3\n",
- "print \"\\n Net work per kg of stem is \",Wt ,\" kJ/kg\"\n",
- "print \"\\n Cycle efficiency is \",n_cycle ,\" percent\"\n",
- "print \"\\n Stream rate is \",sr ,\" kg/kW h\"\n",
- "#The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.6\n",
- "\n",
- "\n",
- " Steam quality at turbine exhaust is 0.90269510582\n",
- "\n",
- " Net work per kg of stem is 798.641701509 kJ/kg\n",
- "\n",
- " Cycle efficiency is 33.3978046046 percent\n",
- "\n",
- " Stream rate is 4.50765342356 kg/kW h\n"
- ]
- }
- ],
- "prompt_number": 6
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.7:pg-501"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "Ti = 2000.0 # Hot gas inlet temperature in K\n",
- "Te = 450.0 # Hot gas exhaust temperature in K\n",
- "T0 = 300.0 # Ambient temperature in K\n",
- "Q1_dot = 100.0 # Heating rate provided by steam in kW\n",
- "cpg = 1.1 # Heat capacity of gas in kJ/kg\n",
- "wg = Q1_dot/(cpg*(Ti-Te)) # mass flow rate of hot gas\n",
- "af1 = wg*cpg*T0*((Ti/T0)-1-log(Ti/T0)) # Availability at inlet\n",
- "af2 = wg*cpg*T0*((Te/T0)-1-log(Te/T0)) # Availability at exit\n",
- "afi = af1-af2 # Change in availability\n",
- "h1 = 2801.0 # Enthalpy at state 1 in kJ/kg\n",
- "h3 = 169.0 #Enthalpy at state 3 in kJ/kg\n",
- "h4 = 172.8 #Enthalpy at state 4 in kJ/kg\n",
- "h2 = 1890.2 # Enthalpy at state 2 in kJ/kg\n",
- "s1 = 6.068 # Entropy at state 1 in kJ/kgK\n",
- "s2 = s1 # Isentropic process\n",
- "s3 = 0.576 # Entropy at state 3 in kJ/kgK\n",
- "s4 = s3 # Isentropic process\n",
- "Wt = h1-h2 # Turbine work\n",
- "Wp = h4-h3 # Pump work\n",
- "Q1 = h1-h4 # Heat addition\n",
- "Q2 = h2-h3# Heat rejection\n",
- "Wnet = Wt-Wp # Net work\n",
- "ws = Q1_dot/2628 # steam mass flow rate\n",
- "afu = 38*(h1-h4-T0*(s1-s3)) # availability loss\n",
- "I_dot = afi-afu # Rate of exergy destruction\n",
- "Wnet_dot = ws*Wnet# Mechanical power rate\n",
- "afc = ws*(h2-h3-T0*(s2-s3)) # Exergy flow rate of of wet steam\n",
- "n2 = 100*Wnet_dot/af1 # second law efficiency\n",
- "\n",
- "print \"\\n Example 12.7\\n\"\n",
- "print \"\\n The second law efficiency is \",n2 ,\" percent\"\n",
- "#The answers vary due to round off error\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.7\n",
- "\n",
- "\n",
- " The second law efficiency is 47.3045857486 percent\n"
- ]
- }
- ],
- "prompt_number": 8
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.8:pg-503"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "# Part (a)\n",
- "h1 = 2758.0 # Enthalpy at state 1 in kJ/kg\n",
- "h2 = 1817.0 # Enthalpy at state 2 in kJ/kg\n",
- "h3 = 192.0 # Enthalpy at state 3 in kJ/kg\n",
- "h4 = 200.0# Enthalpy at state 4 in kJ/kg\n",
- "Wt = h1-h2 # turbine work\n",
- "Wp = h4-h3 # Pump work\n",
- "Q1 = h1-h4 # Heat addition\n",
- "Wnet = Wt-Wp # Net work doen\n",
- "n1 = Wnet/Q1 # First law efficiency\n",
- "WR = Wnet/Wt # Work ratio\n",
- "Q1_ = 100.0 # Heat addition rate in MW\n",
- "PO = n1*Q1_ # power output\n",
- "cpg = 1000 # Specific heat capacity in J/kg\n",
- "wg = (Q1_/(833-450)) # mass flow rate of gas\n",
- "EIR = wg*cpg*((833-300)-300*(log(833/300)))/1000 # Exergy input\n",
- "n2 = PO/EIR # Second law efficiency\n",
- "\n",
- "print \"\\n Example 12.8\\n\"\n",
- "print \"\\n Part (a)\"\n",
- "print \"\\n The first law efficiency n1 is \",n1*100\n",
- "print \"\\n The second law efficiency n2 is \",n2*100\n",
- "print \"\\n The work ratio is \",WR\n",
- "# Part (b)\n",
- "h1b = 3398.0 # Enthalpy at state 1 in kJ/kg\n",
- "h2b = 2130.0 # Enthalpy at state 2 in kJ/kg\n",
- "h3b = 192.0 # Enthalpy at state 3 in kJ/kg\n",
- "h4b = 200.0# Enthalpy at state 4 in kJ/kg\n",
- "Wtb = 1268.0 # turbine work in kJ/kg\n",
- "Wpb = 8.0 # Pump work in kJ/kg\n",
- "Q1b = 3198.0# Heat addition rate in kW\n",
- "n1b = (Wtb-Wpb)/Q1b #first law efficiency\n",
- "WRb = (Wtb-Wpb)/Wtb # WOrk ratio\n",
- "EIRb = 59.3 # Exergy input rate in MW\n",
- "Wnetb = Q1_*n1b # net work done\n",
- "\n",
- "n2b = Wnetb/EIRb # Second law efficiency\n",
- "print \"\\n Part (b)\" \n",
- "print \"\\n The first law efficiency n1 is \",n1b*100\n",
- "print \"\\n The second law efficiency n2 is \",n2b*100\n",
- "print \"\\n The work ration is \",WRb\n",
- "\n",
- "# Part (c)\n",
- "h1c = 3398.0 # Enthalpy at state 1 in kJ/kg\n",
- "h2c = 2761.0 # Enthalpy at state 2 in kJ/kg\n",
- "h3c = 3482.0# Enthalpy at state 3 in kJ/kg\n",
- "h4c = 2522.0 # Enthalpy at state 4 in kJ/kg\n",
- "h5c = 192.0 # Enthalpy at state 5 in kJ/kg\n",
- "h6c = 200.0# Enthalpy at state 6 in kJ/kg\n",
- "Wt1 = 637.0 # Turbine work in kJ/kg\n",
- "Wt2 = 960.0 # Turbine work in kJ/kg\n",
- "Wtc = Wt1+Wt2 # Net turbine work in kJ/kg\n",
- "Wp = 8.0 # Pump work in kJ/kg \n",
- "Wnetc = Wtc-Wp # net work done \n",
- "Q1c = 3198+721 # Heat addition\n",
- "n1c = Wnetc/Q1c# First law efficiency\n",
- "WRc = Wnetc/Wtc# Work ratio\n",
- "POc = Q1_*n1c# Power output\n",
- "EIRc = 59.3# Exergy input in MW\n",
- "n2c = POc/EIRc # Second law efficiency\n",
- "print \"\\n Part (c)\"\n",
- "print \"\\n The first law efficiency n1 is \",n1c*100\n",
- "print \"\\n The second law efficiency n2 is \",n2c*100\n",
- "print \"\\n The work ration is \",WRc\n",
- "\n",
- "# Part (d)\n",
- "T3 = 45.8 # saturation temperature at 0.1 bar in degree celsius \n",
- "T1 = 295.0 # saturation temperature at 80 bar in degree celsius \n",
- "n1d = 1.0-((T3+273)/(T1+273)) # First law efficiency\n",
- "Q1d = 2758-1316 # Heat addition\n",
- "Wnet = Q1d*n1d # Net work output\n",
- "Wpd = 8.0 # Pump work in kJ/kg\n",
- "Wtd = 641.0# Turbine work in kJ/kg\n",
- "WRd = (Wt-Wp)/Wt # Work ratio\n",
- "POd = Q1_*0.439# Power output\n",
- "EIRd = (Q1_/(833-593))*cpg*((833-300)-300*(log(833/300)))/1000 #Exergy Input rate in MW\n",
- "n2d = POd/EIRd # Second law efficiency\n",
- "print \"\\n Part (d)\"\n",
- "print \"\\n The first law efficiency n1 is \",n1d*100\n",
- "print \"\\n The second law efficiency n2 is \",n2d*100\n",
- "print \"\\n The work ration is \",WRd\n",
- "#The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.8\n",
- "\n",
- "\n",
- " Part (a)\n",
- "\n",
- " The first law efficiency n1 is 36.4738076622\n",
- "\n",
- " The second law efficiency n2 is 42.9755948516\n",
- "\n",
- " The work ratio is 0.991498405951\n",
- "\n",
- " Part (b)\n",
- "\n",
- " The first law efficiency n1 is 39.3996247655\n",
- "\n",
- " The second law efficiency n2 is 66.4411884747\n",
- "\n",
- " The work ration is 0.993690851735\n",
- "\n",
- " Part (c)\n",
- "\n",
- " The first law efficiency n1 is 40.5460576678\n",
- "\n",
- " The second law efficiency n2 is 68.3744648698\n",
- "\n",
- " The work ration is 0.994990607389\n",
- "\n",
- " Part (d)\n",
- "\n",
- " The first law efficiency n1 is 43.8732394366\n",
- "\n",
- " The second law efficiency n2 is 32.4128919233\n",
- "\n",
- " The work ration is 0.991498405951\n"
- ]
- }
- ],
- "prompt_number": 10
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.9:pg-505"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "hfg = 2202.6 # Latent heat of fusion in kJ/kg\n",
- "Qh = 5.83 # Heat addition in MJ/s\n",
- "ws = Qh/hfg # steam flow rate\n",
- "eg = 0.9 # efficiency of generator\n",
- "P = 1000.0 # Power generation rate in kW\n",
- "Wnet = 1000.0/eg # Net output\n",
- "nbrake = 0.8 # brake thermal efficiency\n",
- "h1_2s = Wnet/(ws*nbrake) # Ideal heat addition\n",
- "n_internal = 0.85 # internal efficiency\n",
- "h12 = n_internal*h1_2s # Actual heat addition\n",
- "hg = 2706.3 # Enthalpy of gas in kJ/kg\n",
- "h2 = hg #Isenthalpic process \n",
- "h1 = h12+h2 # Total enthalpy \n",
- "h2s = h1-h1_2s # Enthalpy change\n",
- "hf = 503.71 # Enthalpy of fluid in kJ/kg \n",
- "x2s = (h2s-hf)/hfg # Quality of steam\n",
- "sf = 1.5276 # entropy of fluid in kJ/kgK\n",
- "sfg = 5.6020 # Entropy change due to vaporization in kJ/kgK\n",
- "s2s = sf+(x2s*sfg) # Entropy at state 2s\n",
- "s1 = s2s # Isentropic process\n",
- "P1 = 22.5 # Turbine inlet pressure in bar from Mollier chart\n",
- "t1 = 360.0 # Temperature of the steam in degree Celsius from Mollier chart\n",
- "\n",
- "print \"\\n Example 12.9\\n\"\n",
- "print \"\\n Temperature of the steam is \",t1 ,\" degree celcius\"\n",
- "print \"\\n Pressure of the steam is \",P1 ,\" bar\"\n",
- "#The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.9\n",
- "\n",
- "\n",
- " Temperature of the steam is 360.0 degree celcius\n",
- "\n",
- " Pressure of the steam is 22.5 bar\n"
- ]
- }
- ],
- "prompt_number": 11
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.10:pg-506"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "h1 = 3037.3 # Enthalpy at state 1 in kJ/kg\n",
- "x = 0.96 # Steam quality\n",
- "h2 = 561+(x*2163.8) # Enthalpy at state 2 \n",
- "s2 = 1.6718+(x*5.3201)# Entropy at state 2 \n",
- "s3s = s2 # Isentropic process\n",
- "x3s = (s3s-0.6493)/7.5009 # Quality at state 3s \n",
- "h3s = 191.83+(x3s*2392.8) # Enthalpy at state 3s \n",
- "h23 = 0.8*(h2-h3s) # Enthalpy change in process 23\n",
- "h3 = h2-h23 # Enthalpy at state 3\n",
- "h5 = 561.47 # Enthalpy at state 5\n",
- "h4 = 191.83# Enthalpy at state 4\n",
- "Qh = 3500 # Heat addition in kJ/s\n",
- "w = Qh/(h2-h5) # mass flow rate\n",
- "Wt = 1500 # Turbine work\n",
- "ws = (Wt+w*(h2-h3))/(h1-h3) # Steam flow rate \n",
- "ws_ = 3600*ws # Steam flow rate in kg/h\n",
- "h6 = ((ws-w)*h4+w*h5)/ws #Enthalpy at state 6\n",
- "h7 = h6# Enthalpy at state 7\n",
- "n_boiler = 0.85 # Boiler efficiency\n",
- "CV = 44000 # Calorific value of fuel in kJ/kg\n",
- "wf = (1.1*ws_*(h1-h7))/(n_boiler*CV) # Fuel consumption rate\n",
- "\n",
- "print \"\\n Example 12.10\\n\"\n",
- "print \"\\n Fuel burning rate is \",wf*24/1000 ,\" tonnes/day\"\n",
- "#The answers vary due to round off error\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.10\n",
- "\n",
- "\n",
- " Fuel burning rate is 18.1592477786 tonnes/day\n"
- ]
- }
- ],
- "prompt_number": 12
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.11:pg-508"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "h1 = 3285.0 # Enthalpy at state 1 in kJ/kg\n",
- "h2s = 3010.0 # Enthalpy at state 2s in kJ/kg\n",
- "h3 = 3280.0 # # Enthalpy at state 3 in kJ/kg\n",
- "h4s = 3030.0 # # Enthalpy at state 4s in kJ/kg\n",
- "# Saturation pressure at temperature 180 degree centigrade\n",
- "psat = 10 # In bar\n",
- "h4 = h3-0.83*(h3-h4s) # # Enthalpy at state 4 \n",
- "h5s = 2225.0 # # Enthalpy at state 5s in kJ/kg\n",
- "h5 = h4-0.83*(h4-h5s) # # Enthalpy at state 5\n",
- "h6 = 162.7 # Enthalpy at state 6 in kJ/kg\n",
- "h7 = h6 # # Enthalpy at state 7 \n",
- "h8 = 762.81# Enthalpy at state 8 in kJ/kg\n",
- "h2 = h1-0.785*(h1-h2s) #Enthalpy at state 2 \n",
- "m = (h8-h7)/(h4-h7) # regenerative mass flow\n",
- "n_cycle = ((h1-h2)+(h3-h4)+(1-m)*(h4-h5))/((h1-h8)+(h3-h2)) # Cycle efficiency\n",
- "\n",
- "print \"\\n Example 12.11\\n\"\n",
- "print \"\\n The minimum pressure at which bleeding is neccessary is \",psat ,\" bar\"\n",
- "print \"\\n Steam flow at turbine inlet is \",m ,\" kg/s\"\n",
- "print \"\\n Cycle efficiency is \",n_cycle*100 ,\" percent\"\n",
- "#The answers vary due to round off error\n",
- "# Part A and Part B are theoretical problems\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.11\n",
- "\n",
- "\n",
- " The minimum pressure at which bleeding is neccessary is 10 bar\n",
- "\n",
- " Steam flow at turbine inlet is 0.206237542099 kg/s\n",
- "\n",
- " Cycle efficiency is 35.9203808526 percent\n"
- ]
- }
- ],
- "prompt_number": 13
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Ex12.12:pg-510"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "\n",
- "# From table \n",
- "h1 = 2792.2 # Enthalpy at state 1 in kJ/kg \n",
- "h4 = 122.96# Enthalpy at state 4 in kJ/kg \n",
- "hb = 254.88 # Enthalpy at state b in kJ/kg \n",
- "hc = 29.98# Enthalpy at state c in kJ/kg \n",
- "ha = 355.98 # Enthalpy at state a in kJ/kg \n",
- "hd = hc # Isenthalpic process\n",
- "h2 = 1949.27 # # Enthalpy at state 2 in kJ/kg \n",
- "#\n",
- "m = (h1-h4)/(hb-hc) # Amount of mercury circulating\n",
- "Q1t = m*(ha-hd) # Heat addition\n",
- "W1t = m*(ha-hb) + (h1-h2) # Turbine work\n",
- "n = W1t/Q1t # first law efficiency\n",
- "\n",
- "print \"\\n Example 12.12 \\n\"\n",
- "print \"\\n Overall efficiency of the cycle is \",n*100 ,\" percent\"\n",
- "#The answers vary due to round off error\n",
- "\n",
- "S = 50000 # Stem flow rate through turbine in kg/h\n",
- "wm = S*m # mercury flow rate\n",
- "print \"\\n Flow through the mercury turbine is math.exp kg/h\",wm\n",
- "\n",
- "Wt = W1t*S/3600 # Turbine work\n",
- "print \"\\n Useful work done in binary vapor cycle is \",Wt/1e3 ,\" MW\"\n",
- "nm = 0.85 # Internal efficiency of mercury turbine\n",
- "ns = 0.87 # Internal efficiency of steam turbine\n",
- "WTm = nm*(ha-hb) # turbine work of mercury based cycle\n",
- "hb_ = ha-WTm # Enthalpy at state b in kJ/kg\n",
- "m_ = (h1-h4)/(hb_-hc) # mass flow rate of mercury\n",
- "h1_ = 3037.3 # Enthalpy at state 1 in kJ/kg\n",
- "Q1t = m_*(ha-hd)+(h1_-h1) # Heat addition\n",
- "x2_ = (6.9160-0.4226)/(8.47-0.4226) # steam quality\n",
- "h2_ = 121+(0.806*2432.9) # Enthalpy at state 2 in kJ/kg \n",
- "WTst = ns*(h1_-h2_) # Turbine work\n",
- "WTt = m_*(ha-hb_)+WTst # Total turbine work\n",
- "N = WTt/Q1t #Overall efficiency \n",
- "print \"\\n Overall efficiency is \",N*100 ,\" percent\"\n",
- "# The answers vary due to round off error\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "\n",
- " Example 12.12 \n",
- "\n",
- "\n",
- " Overall efficiency of the cycle is 52.7981817715 percent\n",
- "\n",
- " Flow through the mercury turbine is math.exp kg/h 593428.190307\n",
- "\n",
- " Useful work done in binary vapor cycle is 28.3728027889 MW\n",
- "\n",
- " Overall efficiency is 46.1693685319 percent\n"
- ]
- }
- ],
- "prompt_number": 14
- }
- ],
- "metadata": {}
- }
- ]
-}
\ No newline at end of file +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Chapter 12: Vapour power cycle" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.1:pg-492" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.1\n", + "\n", + " The work required in saturated liquid form is -0.9387 kJ/kg\n", + "\n", + " The work required in saturated vapor form is -520.0 kJ/kg\n" + ] + } + ], + "source": [ + "import math\n", + "# Part (a)\n", + "P1 = 1 # Initial pressure in bar\n", + "P2 = 10 # Final pressure in bar\n", + "vf = 0.001043 # specific volume of liquid in m**3/kg\n", + "Wrev = vf*(P1-P2)*1e5 # Work done\n", + "\n", + "print \"\\n Example 12.1\"\n", + "print \"\\n The work required in saturated liquid form is \",Wrev/1000 ,\" kJ/kg\"\n", + "#The answers vary due to round off error\n", + "\n", + "# Part (b)\n", + "h1 = 2675.5 # Enthalpy at state 1 in kJ/kg\n", + "s1 = 7.3594 # Entropy at state 1 kJ/kgK\n", + "s2 = s1 # Isentropic process\n", + "h2 = 3195.5 # Enthalpy at state 2 kJ/kg\n", + "Wrev1 = h1-h2 # Work done\n", + "print \"\\n The work required in saturated vapor form is \",Wrev1 ,\" kJ/kg\"\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.2:pg-493" + ] + }, + { + "cell_type": "code", + "execution_count": 2, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.2\n", + "\n", + " Net work per kg of steam is 969.599095338 kJ/kg\n", + "\n", + " Cycle efficiency is 32.4996706636 percent\n", + "\n", + "\n", + " Percentage reduction in net work per kg of steam is 20.093190186 percent\n", + "\n", + " Percentage reduction in cycle efficiency is 20.093190186 percent\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3159.3 # Enthalpy at state 1 in kJ/kg\n", + "s1 = 6.9917 # Entropy at state 1 in kJ/kgK\n", + "h3 = 173.88 # Enthalpy at state 3 in kJ/kg\n", + "s3 = 0.5926 # Entropy at state 3 in kJ/kgK\n", + "sfp2 = s3 # Isentropic process\n", + "hfp2 = h3 # Isenthalpic process\n", + "hfgp2 = 2403.1 # Latent heat of vaporization in kJ/kg\n", + "sgp2 = 8.2287 # Entropy of gas in kJ/kgK\n", + "vfp2 = 0.001008 # Specific volume in m**3/kg\n", + "sfgp2 = 7.6361# Entropy of liquid in kJ/kgK\n", + "x2s = (s1-sfp2)/(sfgp2)# Steam quality\n", + "h2s = hfp2+(x2s*hfgp2) # Enthalpy at state 2s\n", + "# Part (a)\n", + "P1 = 20 # Turbine inlet pressure in bar\n", + "P2 = 0.08 # Turbine exit pressure in bar\n", + "h4s = vfp2*(P1-P2)*1e2+h3 # Enthalpy at state 4s\n", + "Wp = h4s-h3 # Pump work\n", + "Wt = h1-h2s # Turbine work\n", + "Wnet = Wt-Wp # Net work \n", + "Q1 = h1-h4s # Heat addition\n", + "n_cycle = Wnet/Q1# Cycle efficiency\n", + "print \"\\n Example 12.2\"\n", + "print \"\\n Net work per kg of steam is \",Wnet ,\" kJ/kg\"\n", + "#The answer provided in the textbook is wrong\n", + "\n", + "print \"\\n Cycle efficiency is \",n_cycle*100 ,\" percent\"\n", + "\n", + "# Part (b)\n", + "n_p = 0.8 # pump efficiency\n", + "n_t = 0.8# Turbine efficiency\n", + "Wp_ = Wp/n_p # Pump work\n", + "Wt_ = Wt*n_t # Turbine work\n", + "Wnet_ = Wt_-Wp_# Net work\n", + "P = 100*((Wnet-Wnet_)/Wnet) # Percentage reduction in net work\n", + "n_cycle_ = Wnet_/Q1 # cycle efficiency\n", + "P_ = 100*((n_cycle-n_cycle_)/n_cycle) #reduction in cycle\n", + "print \"\\n\\n Percentage reduction in net work per kg of steam is \",P ,\" percent\"\n", + "print \"\\n Percentage reduction in cycle efficiency is \",P_ ,\" percent\"\n", + "\n", + "#The answers vary due to round off error\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.3:pg-495" + ] + }, + { + "cell_type": "code", + "execution_count": 3, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.3\n", + "\n", + " The greatest allowable steam pressure at the turbine inlet is 16.832 bar\n", + "\n", + " Rankine cycle efficiency is 31.684100869 percent\n", + "\n", + " Mean temperature of heat addition is 187.657819629 degree celcius\n" + ] + } + ], + "source": [ + "import math\n", + "P1 = 0.08 # Exhaust pressure in bar\n", + "sf = 0.5926 # Entropy of fluid in kJ/kgK\n", + "x2s = 0.85 # Steam quality\n", + "sg = 8.2287 # Entropy of gas in kJ/kgK\n", + "s2s = sf+(x2s*(sg-sf)) # Entropy of mixture at state 2s in kJ/kgK\n", + "s1 = s2s # Isentropic process\n", + "P2 = 16.832 # by steam table opposite to s1 in bar\n", + "h1 = 3165.54 # Enthalpy at state 1 in kJ/kg\n", + "h2s = 173.88 + (0.85*2403.1) # Enthalpy at state 2s in kJ/kg\n", + "h3 = 173.88# Enthalpy at state 3 in kJ/kg\n", + "vfp2 = 0.001 # specific volume of liquid in m**3/kg\n", + "h4s = h3 + (vfp2*(P2-P1)*100)# Enthalpy at state 4s in kJ/kg\n", + "Q1 = h1-h4s # Heat addition\n", + "Wt = h1-h2s # Turbine work\n", + "Wp = h4s-h3 # Pump work\n", + "n_cycle = 100*((Wt-Wp)/Q1) # Cycle efficiency\n", + "Tm = (h1-h4s)/(s2s-sf) # Mean temperature of heat addition\n", + "\n", + "print \"\\n Example 12.3\"\n", + "print \"\\n The greatest allowable steam pressure at the turbine inlet is \",P2 ,\" bar\"\n", + "\n", + "print \"\\n Rankine cycle efficiency is \",n_cycle ,\" percent\"\n", + "\n", + "print \"\\n Mean temperature of heat addition is \",Tm-273 ,\" degree celcius\"\n", + "#The answers vary due to round off error\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.4:pg-496" + ] + }, + { + "cell_type": "code", + "execution_count": 4, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.4 \n", + "\n", + "\n", + " Quality at turbine exhaust is 0.88\n", + "\n", + " Cycle efficiency is 43.9043470625 percent\n", + "\n", + " Steam rate is 2.18181818182 kg/kW h\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3465 # Enthalpy at state 1 in kJ/kgK\n", + "h2s = 3065 #Enthalpy at state 2s in kJ/kgK \n", + "h3 = 3565 #Enthalpy at state 3 in kJ/kgK\n", + "h4s = 2300 # Enthalpy at state 4s in kJ/kgK\n", + "x4s = 0.88 # Steam quality at state 4s\n", + "h5 = 191.83# Enthalpy at state 5 in kJ/kgK\n", + "v = 0.001 # specific volume in m**3/kg\n", + "P = 150 # Boiler outlet pressure in bar\n", + "Wp = v*P*100 # Pump work\n", + "h6s = 206.83 # Enthalpy at state 6s in kJ/kgK\n", + "Q1 = (h1-h6s)+(h3-h2s) # Heat addition\n", + "Wt = (h1-h2s)+(h3-h4s) # Turbine work\n", + "Wnet = Wt-Wp # Net work\n", + "n_cycle = 100*Wnet/Q1 # cycle efficiency\n", + "sr = 3600/Wnet #Steam rate\n", + "\n", + "print \"\\n Example 12.4 \\n\"\n", + "print \"\\n Quality at turbine exhaust is \",0.88\n", + "print \"\\n Cycle efficiency is \",n_cycle ,\" percent\"\n", + "print \"\\n Steam rate is \",sr ,\" kg/kW h\"\n", + "#The answers vary due to round off error\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.5:pg-497" + ] + }, + { + "cell_type": "code", + "execution_count": 5, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.5\n", + "\n", + "\n", + " Efficiency of the cycle is 36.0687573387 percent\n", + "\n", + " Steam rate of the cycle is 3.85264705574 kg/kW h\n", + "\n", + " Increase in temperature due to regeneration is 27.3862065182 degree centigrade\n", + "\n", + " Increase in steam rate due to regeneration is 0.385518227773 kg/kW h\n", + "\n", + " Increase in Efficiency of the cycle due to regeneration is 1.90293971596 percent\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3230.9 # Enthalpy at state 1 in kJ/kg\n", + "s1 = 6.9212 # Entropy at state 1 in kJ/kgK\n", + "s2 = s1 # Isentropic process\n", + "s3 = s1 # Isentropic process\n", + "h2 = 2796 # Enthalpy at state 2 in kJ/kg\n", + "sf = 0.6493 # ENtropy of fluid onkJ/kgK\n", + "sfg = 7.5009 # Entropy change due to vaporization\n", + "x3 = (s3-sf)/sfg # steam quality\n", + "h3 = 191.83 + x3*2392.8 # Enthalpy at state 3\n", + "h4 = 191.83 # Enthalpy at state 4 in kJ/kg\n", + "h5 = h4 # Isenthalpic process\n", + "h6 = 640.23 # Enthalpy at state 6 in kJ/kg\n", + "h7 = h6 # Isenthalpic process\n", + "m = (h6-h5)/(h2-h5) # regenerative mass\n", + "Wt = (h1-h2)+(1-m)*(h2-h3) # turbine work\n", + "Q1 = h1-h6 # Heat addition\n", + "n_cycle = 100*Wt/Q1 # Cycle efficiency\n", + "sr = 3600/Wt # Steam rate\n", + "s7 = 1.8607 # Entropy at state 7 in kJ/kgK\n", + "s4 = 0.6493 # Entropy at state 4 in kJ/kgK \n", + "Tm = (h1-h7)/(s1-s7) # Mean temperature of heat addition with regeneration\n", + "Tm1 = (h1-h4)/(s1-s4) # Mean temperature of heat addition without regeneration\n", + "dT = Tm-Tm1 # Change in temperature\n", + "Wt_ = h1-h3 # Turbine work\n", + "sr_ = 3600/Wt_ # Steam rate\n", + "dsr = sr-sr_# Change in steam rate\n", + "n_cycle_ = 100*(h1-h3)/(h1-h4) # Cycle effciency\n", + "dn = n_cycle-n_cycle_# Change in efficiency\n", + "print \"\\n Example 12.5\\n\"\n", + "print \"\\n Efficiency of the cycle is \",n_cycle ,\" percent\"\n", + "\n", + "print \"\\n Steam rate of the cycle is \",sr ,\" kg/kW h\"\n", + "#The answer provided in the textbook is wrong\n", + "\n", + "print \"\\n Increase in temperature due to regeneration is \",dT ,\" degree centigrade\"\n", + "print \"\\n Increase in steam rate due to regeneration is \",dsr ,\" kg/kW h\"\n", + "#The answer provided in the textbook is wrong\n", + "\n", + "print \"\\n Increase in Efficiency of the cycle due to regeneration is \",dn ,\" percent\"\n", + "\n", + "#The answers vary due to round off error\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.6:pg-499" + ] + }, + { + "cell_type": "code", + "execution_count": 6, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.6\n", + "\n", + "\n", + " Steam quality at turbine exhaust is 0.90269510582\n", + "\n", + " Net work per kg of stem is 798.641701509 kJ/kg\n", + "\n", + " Cycle efficiency is 33.3978046046 percent\n", + "\n", + " Stream rate is 4.50765342356 kg/kW h\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3023.5 # Enthalpy of steam at state 1 in kJ/kg\n", + "s1 = 6.7664 # Enthalpy of steam at state 1 in kJ/kgK\n", + "s2 = s1 # Isentropic process\n", + "s3 = s1 #Isentropic process\n", + "s4 = s1 #Isentropic process\n", + "t_sat_20 = 212 # Saturation temperature at 20 bar in degree Celsius\n", + "t_sat_1 = 46 # Saturation temperature at 1 bar in degree Celsius\n", + "dt = t_sat_20-t_sat_1 # Change in temperature\n", + "n =3 # number of heaters\n", + "t = dt/n # temperature rise per heater\n", + "t1 = t_sat_20-t # Operational temperature of first heater\n", + "t2 = t1-t# Operational temperature of second heater\n", + "# 0.1 bar\n", + "hf = 191.83 # Enthalpy of fluid in kJ/kg\n", + "hfg = 2392.8 # Latent heat of vaporization in kJ/kg\n", + "sf = 0.6493# Entropy of fluid in kJ/kgK\n", + "sg = 8.1502# Entropy of gas in kJ/kgK\n", + "# At 100 degree\n", + "hf100 = 419.04 # Enthalpy of fluid in kJ/kg \n", + "hfg100 = 2257.0# Latent heat of vaporization in kJ/kg \n", + "sf100 = 1.3069 # Entropy of fluid in kJ/kgK \n", + "sg100 = 7.3549 # Entropy of gas in kJ/kgK\n", + "# At 150 degree\n", + "hf150 = 632.20 # Enthalpy of fluid in kJ/kg \n", + "hfg150 = 2114.3# Latent heat of vaporization in kJ/kg \n", + "sf150 = 1.8418 # Entropy of fluid in kJ/kgK \n", + "sg150 = 6.8379# Entropy of gas in kJ/kgK\n", + "x2 = (s1-sf150)/4.9961 # Steam quality\n", + "h2 = hf150+(x2*hfg150) # Enthalpy at state 2 in kJ/kg\n", + "x3 = (s1-sf100)/6.0480 # Steam quality\n", + "h3 = hf100+(x3*hfg100) # Enthalpy at state 3 in kJ/kg \n", + "x4 = (s1-sf)/7.5010 # Steam quality\n", + "h4 = hf+(x4*hfg)#Enthalpy at state 4 in kJ/kg\n", + "h5 = hf # Enthalpy at state 5 in kJ/kg\n", + "h6 = h5 #Enthalpy at state 6 in kJ/kg\n", + "h7 = hf100 # Enthalpy at state 7 in kJ/kg\n", + "h8 = h7 # Enthalpy at state 8 in kJ/kg\n", + "h9 = 632.2 # Enthalpy at state 9 in kJ/kg\n", + "h10 = h9 # Enthalpy at state 10 in kJ/kg\n", + "m1 = (h9-h7)/(h2-h7) # regenerative mass \n", + "m2 = ((1-m1)*(h7-h6))/(h3-h6) # regenerative mass\n", + "Wt = 1*(h1-h2)+(1-m1)*(h2-h3)+(1-m1-m2)*(h3-h4) # Turbine work\n", + "Q1 = h1-h9 # Heat addition\n", + "Wp = 0 # Pump work is neglected\n", + "n_cycle = 100*(Wt-Wp)/Q1 # Cycle efficiency\n", + "sr = 3600/(Wt-Wp) # Steam rate\n", + "\n", + "print \"\\n Example 12.6\\n\"\n", + "print \"\\n Steam quality at turbine exhaust is \",x3\n", + "print \"\\n Net work per kg of stem is \",Wt ,\" kJ/kg\"\n", + "print \"\\n Cycle efficiency is \",n_cycle ,\" percent\"\n", + "print \"\\n Stream rate is \",sr ,\" kg/kW h\"\n", + "#The answers vary due to round off error\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.7:pg-501" + ] + }, + { + "cell_type": "code", + "execution_count": 8, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.7\n", + "\n", + "\n", + " The second law efficiency is 47.3045857486 percent\n" + ] + } + ], + "source": [ + "import math\n", + "Ti = 2000.0 # Hot gas inlet temperature in K\n", + "Te = 450.0 # Hot gas exhaust temperature in K\n", + "T0 = 300.0 # Ambient temperature in K\n", + "Q1_dot = 100.0 # Heating rate provided by steam in kW\n", + "cpg = 1.1 # Heat capacity of gas in kJ/kg\n", + "wg = Q1_dot/(cpg*(Ti-Te)) # mass flow rate of hot gas\n", + "af1 = wg*cpg*T0*((Ti/T0)-1-math.log(Ti/T0)) # Availability at inlet\n", + "af2 = wg*cpg*T0*((Te/T0)-1-math.log(Te/T0)) # Availability at exit\n", + "afi = af1-af2 # Change in availability\n", + "h1 = 2801.0 # Enthalpy at state 1 in kJ/kg\n", + "h3 = 169.0 #Enthalpy at state 3 in kJ/kg\n", + "h4 = 172.8 #Enthalpy at state 4 in kJ/kg\n", + "h2 = 1890.2 # Enthalpy at state 2 in kJ/kg\n", + "s1 = 6.068 # Entropy at state 1 in kJ/kgK\n", + "s2 = s1 # Isentropic process\n", + "s3 = 0.576 # Entropy at state 3 in kJ/kgK\n", + "s4 = s3 # Isentropic process\n", + "Wt = h1-h2 # Turbine work\n", + "Wp = h4-h3 # Pump work\n", + "Q1 = h1-h4 # Heat addition\n", + "Q2 = h2-h3# Heat rejection\n", + "Wnet = Wt-Wp # Net work\n", + "ws = Q1_dot/2628 # steam mass flow rate\n", + "afu = 38*(h1-h4-T0*(s1-s3)) # availability loss\n", + "I_dot = afi-afu # Rate of exergy destruction\n", + "Wnet_dot = ws*Wnet# Mechanical power rate\n", + "afc = ws*(h2-h3-T0*(s2-s3)) # Exergy flow rate of of wet steam\n", + "n2 = 100*Wnet_dot/af1 # second law efficiency\n", + "\n", + "print \"\\n Example 12.7\\n\"\n", + "print \"\\n The second law efficiency is \",n2 ,\" percent\"\n", + "#The answers vary due to round off error\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.8:pg-503" + ] + }, + { + "cell_type": "code", + "execution_count": 10, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.8\n", + "\n", + "\n", + " Part (a)\n", + "\n", + " The first law efficiency n1 is 36.4738076622\n", + "\n", + " The second law efficiency n2 is 42.9755948516\n", + "\n", + " The work ratio is 0.991498405951\n", + "\n", + " Part (b)\n", + "\n", + " The first law efficiency n1 is 39.3996247655\n", + "\n", + " The second law efficiency n2 is 66.4411884747\n", + "\n", + " The work ration is 0.993690851735\n", + "\n", + " Part (c)\n", + "\n", + " The first law efficiency n1 is 40.5460576678\n", + "\n", + " The second law efficiency n2 is 68.3744648698\n", + "\n", + " The work ration is 0.994990607389\n", + "\n", + " Part (d)\n", + "\n", + " The first law efficiency n1 is 43.8732394366\n", + "\n", + " The second law efficiency n2 is 32.4128919233\n", + "\n", + " The work ration is 0.991498405951\n" + ] + } + ], + "source": [ + "import math\n", + "# Part (a)\n", + "h1 = 2758.0 # Enthalpy at state 1 in kJ/kg\n", + "h2 = 1817.0 # Enthalpy at state 2 in kJ/kg\n", + "h3 = 192.0 # Enthalpy at state 3 in kJ/kg\n", + "h4 = 200.0# Enthalpy at state 4 in kJ/kg\n", + "Wt = h1-h2 # turbine work\n", + "Wp = h4-h3 # Pump work\n", + "Q1 = h1-h4 # Heat addition\n", + "Wnet = Wt-Wp # Net work doen\n", + "n1 = Wnet/Q1 # First law efficiency\n", + "WR = Wnet/Wt # Work ratio\n", + "Q1_ = 100.0 # Heat addition rate in MW\n", + "PO = n1*Q1_ # power output\n", + "cpg = 1000 # Specific heat capacity in J/kg\n", + "wg = (Q1_/(833-450)) # mass flow rate of gas\n", + "EIR = wg*cpg*((833-300)-300*(math.log(833/300)))/1000 # Exergy input\n", + "n2 = PO/EIR # Second law efficiency\n", + "\n", + "print \"\\n Example 12.8\\n\"\n", + "print \"\\n Part (a)\"\n", + "print \"\\n The first law efficiency n1 is \",n1*100\n", + "print \"\\n The second law efficiency n2 is \",n2*100\n", + "print \"\\n The work ratio is \",WR\n", + "# Part (b)\n", + "h1b = 3398.0 # Enthalpy at state 1 in kJ/kg\n", + "h2b = 2130.0 # Enthalpy at state 2 in kJ/kg\n", + "h3b = 192.0 # Enthalpy at state 3 in kJ/kg\n", + "h4b = 200.0# Enthalpy at state 4 in kJ/kg\n", + "Wtb = 1268.0 # turbine work in kJ/kg\n", + "Wpb = 8.0 # Pump work in kJ/kg\n", + "Q1b = 3198.0# Heat addition rate in kW\n", + "n1b = (Wtb-Wpb)/Q1b #first law efficiency\n", + "WRb = (Wtb-Wpb)/Wtb # WOrk ratio\n", + "EIRb = 59.3 # Exergy input rate in MW\n", + "Wnetb = Q1_*n1b # net work done\n", + "\n", + "n2b = Wnetb/EIRb # Second law efficiency\n", + "print \"\\n Part (b)\" \n", + "print \"\\n The first law efficiency n1 is \",n1b*100\n", + "print \"\\n The second law efficiency n2 is \",n2b*100\n", + "print \"\\n The work ration is \",WRb\n", + "\n", + "# Part (c)\n", + "h1c = 3398.0 # Enthalpy at state 1 in kJ/kg\n", + "h2c = 2761.0 # Enthalpy at state 2 in kJ/kg\n", + "h3c = 3482.0# Enthalpy at state 3 in kJ/kg\n", + "h4c = 2522.0 # Enthalpy at state 4 in kJ/kg\n", + "h5c = 192.0 # Enthalpy at state 5 in kJ/kg\n", + "h6c = 200.0# Enthalpy at state 6 in kJ/kg\n", + "Wt1 = 637.0 # Turbine work in kJ/kg\n", + "Wt2 = 960.0 # Turbine work in kJ/kg\n", + "Wtc = Wt1+Wt2 # Net turbine work in kJ/kg\n", + "Wp = 8.0 # Pump work in kJ/kg \n", + "Wnetc = Wtc-Wp # net work done \n", + "Q1c = 3198+721 # Heat addition\n", + "n1c = Wnetc/Q1c# First law efficiency\n", + "WRc = Wnetc/Wtc# Work ratio\n", + "POc = Q1_*n1c# Power output\n", + "EIRc = 59.3# Exergy input in MW\n", + "n2c = POc/EIRc # Second law efficiency\n", + "print \"\\n Part (c)\"\n", + "print \"\\n The first law efficiency n1 is \",n1c*100\n", + "print \"\\n The second law efficiency n2 is \",n2c*100\n", + "print \"\\n The work ration is \",WRc\n", + "\n", + "# Part (d)\n", + "T3 = 45.8 # saturation temperature at 0.1 bar in degree celsius \n", + "T1 = 295.0 # saturation temperature at 80 bar in degree celsius \n", + "n1d = 1.0-((T3+273)/(T1+273)) # First law efficiency\n", + "Q1d = 2758-1316 # Heat addition\n", + "Wnet = Q1d*n1d # Net work output\n", + "Wpd = 8.0 # Pump work in kJ/kg\n", + "Wtd = 641.0# Turbine work in kJ/kg\n", + "WRd = (Wt-Wp)/Wt # Work ratio\n", + "POd = Q1_*0.439# Power output\n", + "EIRd = (Q1_/(833-593))*cpg*((833-300)-300*(math.log(833/300)))/1000 #Exergy Input rate in MW\n", + "n2d = POd/EIRd # Second law efficiency\n", + "print \"\\n Part (d)\"\n", + "print \"\\n The first law efficiency n1 is \",n1d*100\n", + "print \"\\n The second law efficiency n2 is \",n2d*100\n", + "print \"\\n The work ration is \",WRd\n", + "#The answers vary due to round off error\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.9:pg-505" + ] + }, + { + "cell_type": "code", + "execution_count": 11, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.9\n", + "\n", + "\n", + " Temperature of the steam is 360.0 degree celcius\n", + "\n", + " Pressure of the steam is 22.5 bar\n" + ] + } + ], + "source": [ + "import math\n", + "hfg = 2202.6 # Latent heat of fusion in kJ/kg\n", + "Qh = 5.83 # Heat addition in MJ/s\n", + "ws = Qh/hfg # steam flow rate\n", + "eg = 0.9 # efficiency of generator\n", + "P = 1000.0 # Power generation rate in kW\n", + "Wnet = 1000.0/eg # Net output\n", + "nbrake = 0.8 # brake thermal efficiency\n", + "h1_2s = Wnet/(ws*nbrake) # Ideal heat addition\n", + "n_internal = 0.85 # internal efficiency\n", + "h12 = n_internal*h1_2s # Actual heat addition\n", + "hg = 2706.3 # Enthalpy of gas in kJ/kg\n", + "h2 = hg #Isenthalpic process \n", + "h1 = h12+h2 # Total enthalpy \n", + "h2s = h1-h1_2s # Enthalpy change\n", + "hf = 503.71 # Enthalpy of fluid in kJ/kg \n", + "x2s = (h2s-hf)/hfg # Quality of steam\n", + "sf = 1.5276 # entropy of fluid in kJ/kgK\n", + "sfg = 5.6020 # Entropy change due to vaporization in kJ/kgK\n", + "s2s = sf+(x2s*sfg) # Entropy at state 2s\n", + "s1 = s2s # Isentropic process\n", + "P1 = 22.5 # Turbine inlet pressure in bar from Mollier chart\n", + "t1 = 360.0 # Temperature of the steam in degree Celsius from Mollier chart\n", + "\n", + "print \"\\n Example 12.9\\n\"\n", + "print \"\\n Temperature of the steam is \",t1 ,\" degree celcius\"\n", + "print \"\\n Pressure of the steam is \",P1 ,\" bar\"\n", + "#The answers vary due to round off error\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.10:pg-506" + ] + }, + { + "cell_type": "code", + "execution_count": 12, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.10\n", + "\n", + "\n", + " Fuel burning rate is 18.1592477786 tonnes/day\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3037.3 # Enthalpy at state 1 in kJ/kg\n", + "x = 0.96 # Steam quality\n", + "h2 = 561+(x*2163.8) # Enthalpy at state 2 \n", + "s2 = 1.6718+(x*5.3201)# Entropy at state 2 \n", + "s3s = s2 # Isentropic process\n", + "x3s = (s3s-0.6493)/7.5009 # Quality at state 3s \n", + "h3s = 191.83+(x3s*2392.8) # Enthalpy at state 3s \n", + "h23 = 0.8*(h2-h3s) # Enthalpy change in process 23\n", + "h3 = h2-h23 # Enthalpy at state 3\n", + "h5 = 561.47 # Enthalpy at state 5\n", + "h4 = 191.83# Enthalpy at state 4\n", + "Qh = 3500 # Heat addition in kJ/s\n", + "w = Qh/(h2-h5) # mass flow rate\n", + "Wt = 1500 # Turbine work\n", + "ws = (Wt+w*(h2-h3))/(h1-h3) # Steam flow rate \n", + "ws_ = 3600*ws # Steam flow rate in kg/h\n", + "h6 = ((ws-w)*h4+w*h5)/ws #Enthalpy at state 6\n", + "h7 = h6# Enthalpy at state 7\n", + "n_boiler = 0.85 # Boiler efficiency\n", + "CV = 44000 # Calorific value of fuel in kJ/kg\n", + "wf = (1.1*ws_*(h1-h7))/(n_boiler*CV) # Fuel consumption rate\n", + "\n", + "print \"\\n Example 12.10\\n\"\n", + "print \"\\n Fuel burning rate is \",wf*24/1000 ,\" tonnes/day\"\n", + "#The answers vary due to round off error\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.11:pg-508" + ] + }, + { + "cell_type": "code", + "execution_count": 13, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.11\n", + "\n", + "\n", + " The minimum pressure at which bleeding is neccessary is 10 bar\n", + "\n", + " Steam flow at turbine inlet is 0.206237542099 kg/s\n", + "\n", + " Cycle efficiency is 35.9203808526 percent\n" + ] + } + ], + "source": [ + "import math\n", + "h1 = 3285.0 # Enthalpy at state 1 in kJ/kg\n", + "h2s = 3010.0 # Enthalpy at state 2s in kJ/kg\n", + "h3 = 3280.0 # # Enthalpy at state 3 in kJ/kg\n", + "h4s = 3030.0 # # Enthalpy at state 4s in kJ/kg\n", + "# Saturation pressure at temperature 180 degree centigrade\n", + "psat = 10 # In bar\n", + "h4 = h3-0.83*(h3-h4s) # # Enthalpy at state 4 \n", + "h5s = 2225.0 # # Enthalpy at state 5s in kJ/kg\n", + "h5 = h4-0.83*(h4-h5s) # # Enthalpy at state 5\n", + "h6 = 162.7 # Enthalpy at state 6 in kJ/kg\n", + "h7 = h6 # # Enthalpy at state 7 \n", + "h8 = 762.81# Enthalpy at state 8 in kJ/kg\n", + "h2 = h1-0.785*(h1-h2s) #Enthalpy at state 2 \n", + "m = (h8-h7)/(h4-h7) # regenerative mass flow\n", + "n_cycle = ((h1-h2)+(h3-h4)+(1-m)*(h4-h5))/((h1-h8)+(h3-h2)) # Cycle efficiency\n", + "\n", + "print \"\\n Example 12.11\\n\"\n", + "print \"\\n The minimum pressure at which bleeding is neccessary is \",psat ,\" bar\"\n", + "print \"\\n Steam flow at turbine inlet is \",m ,\" kg/s\"\n", + "print \"\\n Cycle efficiency is \",n_cycle*100 ,\" percent\"\n", + "#The answers vary due to round off error\n", + "# Part A and Part B are theoretical problems\n", + "\n" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Ex12.12:pg-510" + ] + }, + { + "cell_type": "code", + "execution_count": 14, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "\n", + " Example 12.12 \n", + "\n", + "\n", + " Overall efficiency of the cycle is 52.7981817715 percent\n", + "\n", + " Flow through the mercury turbine is math.exp kg/h 593428.190307\n", + "\n", + " Useful work done in binary vapor cycle is 28.3728027889 MW\n", + "\n", + " Overall efficiency is 46.1693685319 percent\n" + ] + } + ], + "source": [ + "import math\n", + "# From table \n", + "h1 = 2792.2 # Enthalpy at state 1 in kJ/kg \n", + "h4 = 122.96# Enthalpy at state 4 in kJ/kg \n", + "hb = 254.88 # Enthalpy at state b in kJ/kg \n", + "hc = 29.98# Enthalpy at state c in kJ/kg \n", + "ha = 355.98 # Enthalpy at state a in kJ/kg \n", + "hd = hc # Isenthalpic process\n", + "h2 = 1949.27 # # Enthalpy at state 2 in kJ/kg \n", + "#\n", + "m = (h1-h4)/(hb-hc) # Amount of mercury circulating\n", + "Q1t = m*(ha-hd) # Heat addition\n", + "W1t = m*(ha-hb) + (h1-h2) # Turbine work\n", + "n = W1t/Q1t # first law efficiency\n", + "\n", + "print \"\\n Example 12.12 \\n\"\n", + "print \"\\n Overall efficiency of the cycle is \",n*100 ,\" percent\"\n", + "#The answers vary due to round off error\n", + "\n", + "S = 50000 # Stem flow rate through turbine in kg/h\n", + "wm = S*m # mercury flow rate\n", + "print \"\\n Flow through the mercury turbine is math.exp kg/h\",wm\n", + "\n", + "Wt = W1t*S/3600 # Turbine work\n", + "print \"\\n Useful work done in binary vapor cycle is \",Wt/1e3 ,\" MW\"\n", + "nm = 0.85 # Internal efficiency of mercury turbine\n", + "ns = 0.87 # Internal efficiency of steam turbine\n", + "WTm = nm*(ha-hb) # turbine work of mercury based cycle\n", + "hb_ = ha-WTm # Enthalpy at state b in kJ/kg\n", + "m_ = (h1-h4)/(hb_-hc) # mass flow rate of mercury\n", + "h1_ = 3037.3 # Enthalpy at state 1 in kJ/kg\n", + "Q1t = m_*(ha-hd)+(h1_-h1) # Heat addition\n", + "x2_ = (6.9160-0.4226)/(8.47-0.4226) # steam quality\n", + "h2_ = 121+(0.806*2432.9) # Enthalpy at state 2 in kJ/kg \n", + "WTst = ns*(h1_-h2_) # Turbine work\n", + "WTt = m_*(ha-hb_)+WTst # Total turbine work\n", + "N = WTt/Q1t #Overall efficiency \n", + "print \"\\n Overall efficiency is \",N*100 ,\" percent\"\n", + "# The answers vary due to round off error\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 +} |