{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Chapter 2 : Analysis of Steam Cycles"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.1 Pg: 82"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"(a)Power output of the cycle is 1746.3 kW \n",
" Efficiency of the cycle is 35.1 percent \n",
"\n",
" (b)Without geothermal heat supply \n",
" Power output of the cycle is 955.17 kW \n",
" Efficiency of the cycle is 19.22 percent\n"
]
}
],
"source": [
"#Input data\n",
"p1=40#Initial pressure of steam in bar\n",
"T1=500#Initial temperature of steam in degree C\n",
"m1=5500#Rate of steam in kg/h\n",
"p2=2#Pressure of steam after expansion in bar\n",
"n1=0.83#Isentropic efficiency \n",
"q=0.87#Quality\n",
"m2=2700#Mass flow rate in kg/h\n",
"p3=0.1#Pressure of steam after expansion in l.p turbine in bar\n",
"n2=0.78#Isentropic efficiency\n",
"\n",
"#Calculations\n",
"h1=3445.3#Enthalpy in kJ/kg\n",
"s1=7.0901#Entropy in kJ/kg.K which is 1.5301+x2s*5.5970\n",
"x2s=(5.5600/5.5970)#dryness fraction\n",
"h2s=(504.7+(x2s*2201.9))#Enthalpy in kJ/kg\n",
"h2=h1-(n1*(h1-h2s))#Enthalpy in kJ/kg\n",
"h3=(504.7+(q*2201.9))#Enthalpy in kJ/kg\n",
"h4=((m2*h3+m1*h2)/(m1+m2))#Enthalpy in kJ/kg\n",
"x4=(2183.78/2201.9)#dryness fraction\n",
"s4=(1.5301+x4*5.5970)#Entropy in kJ/kg.K\n",
"x5s=0.8574#dryness fraction\n",
"h5s=(191.84+x5s*2392.5)#Enthalpy in kJ/kg\n",
"dh4h5=(n2*(h4-h5s))#Difference in enthalpy (h4-h5) in kJ/kg\n",
"h6=191.83#Enthalpy in kJ/kg\n",
"W1=((m1*(h1-h2))+((m1+m2)*dh4h5))/3600#Power output of the plant in kW\n",
"Q1=(m1*(h1-h6))/3600#Heat input in kW\n",
"n1=(W1/Q1)*100#Efficiency in percent\n",
"WT=(m1*(h1-h2))/3600#Power output without the geothermal heat supply in kW\n",
"Q2=(m1*(h1-h6))/3600#Heat input without the geothermal heat supply in kW\n",
"n2=(WT/Q2)*100#Efficiency of the cycle without the geothermal heat supply in percent\n",
"\n",
"#Output\n",
"print \"(a)Power output of the cycle is %3.1f kW \\n Efficiency of the cycle is %3.1f percent \\n\\n (b)Without geothermal heat supply \\n Power output of the cycle is %3.2f kW \\n Efficiency of the cycle is %3.2f percent\"%(W1,n1,WT,n2)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.2 Pg: 83"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"(a)Mass flow rate of steam at turbine inlet is 452 kg/s \n",
" (b)The cycle efficiency is 38.82 percent \n",
" (c)Work ratio is 0.999\n"
]
}
],
"source": [
"#Input data\n",
"p1=90#Initial pressure of steam in bar\n",
"T1=500#Initial temperature of steam in degree C\n",
"O=(500*1000)#Output in kW\n",
"T2=40#Condensation temperature in degree C\n",
"nhp=0.92#Efficiency of h.p turbine\n",
"nlp=0.9#Efficiency of l.p turbine\n",
"np=0.75#Isentropic efficiency of the pump \n",
"TTD=-1.6#Temperature in degree C\n",
"\n",
"#Calculations\n",
"p2=(0.2*p1)#Optimum reheat pressure in bar\n",
"h1=3386.1#Enthalpy in kJ/kg\n",
"s1=6.6576#Entropy in kJ/kg.K\n",
"s2s=s1#Entropy in kJ/kg.K\n",
"h2s=2915#Enthalpy in kJ/kg\n",
"h3=3469.8#Enthalpy in kJ/kg\n",
"s3=7.4825#Entropy in kJ/kg.K\n",
"x4s=(s3-0.5725)/7.6845#Dryness fraction\n",
"h4s=(167.57+x4s*2406.7)#Enthalpy in kJ/kg\n",
"h5=167.57#Enthalpy in kJ/kg\n",
"h7=883.42#Enthalpy in kJ/kg\n",
"Wps=(0.001008*p1*10)#Workdone by the pump in kJ/kg\n",
"h6s=176.64#Enthalpy in kJ/kg\n",
"dh1h2=(nhp*(h1-h2s))#Difference in enthalpy (h1-h2) in kJ/kg\n",
"h2=h1-dh1h2#Enthalpy in kJ/kg\n",
"dh3h4=(nlp*(h3-h4s))#Difference in enthalpy (h3-h4) in kJ/kg\n",
"h4=h3-dh3h4#Enthalpy in kJ/kg\n",
"Wp=(Wps/np)#Workdone by the pump in kJ/kg\n",
"h6=(Wp+h5)#Enthalpy in kJ/kg\n",
"tsat=207.15#Saturation temperature at 18 bar in degree C\n",
"t9=(tsat-TTD)#Temperature in degree C\n",
"h9=875#Enthalpy in kJ/kg\n",
"m=((h9-h6)/(h2-h7))#Mass of steam in kg\n",
"WT=(dh1h2+(1-m)*dh3h4)#Workdone by the turbine in kJ/kg\n",
"Wnet=(WT-Wp)#Net workdone in kJ/kg\n",
"ws=(O/Wnet)#Mass flow rate of steam at turbine inlet in kg/s\n",
"Q1=((h1-h9)+(1-m)*(h3-h2))#Heat input in kJ/kg\n",
"n=(Wnet/Q1)*100#Efficiency of the cycle in percent\n",
"Wr=(Wnet/WT)#Work ratio\n",
"\n",
"#Output\n",
"print \"(a)Mass flow rate of steam at turbine inlet is %3.0f kg/s \\n (b)The cycle efficiency is %3.2f percent \\n (c)Work ratio is %3.3f\"%(ws,n,Wr)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.3 Pg: 86"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"The optimum pressure and temperature at different heaters are: \n",
" Heater 1: t1 = 255.2 degree C and p1 = 4.33 MPa\n",
" Heater 2: t2 = 224.5 degree C and p2 = 2.5318 MPa\n",
" Heater 3: t3 = 193.8 degree C and p3 = 1.367 MPa\n",
" Heater 4: t4 = 163.1 degree C and p4 = 0.6714 MPa\n",
" Heater 5: t5 = 132.4 degree C and p5 = 0.2906 MPa\n",
" Heater 6: t6 = 101.7 degree C and p6 = 0.108 MPa\n",
" Heater 7: t7 = 71.0 degree C and p7 = 32.65 kPa\n"
]
}
],
"source": [
"#Input data\n",
"p1=70#Pressure at which an ideal seam power plant operates in bar\n",
"T1=550#Temperature at which an ideal seam power plant operates in degrees C\n",
"p2=0.075#Pressure at which an ideal seam power plant operates in bar\n",
"\n",
"#Calculations\n",
"TB=285.9#Saturation temperature at 70 bar in degree C\n",
"TC=40.3#Saturation temperature at 0.075 bar in degree C\n",
"Tr=(TB-TC)/(7+1)#Temperature rise per heater for maximum cycle efficiency in degree C\n",
"t1=(TB-Tr)#Temperature at heater 1 in degree C\n",
"P1=4.33#Pressure at heater 1 in MPa\n",
"t2=(t1-Tr)#Temperature at heater 2 in degree C\n",
"P2=2.5318#Pressure at heater 2 in MPa\n",
"t3=(t2-Tr)#Temperature at heater 3 in degree C\n",
"P3=1.367#Pressure at heater 3 in MPa\n",
"t4=(t3-Tr)#Temperature at heater 4 in degree C\n",
"P4=0.6714#Pressure at heater 4 in MPa\n",
"t5=(t4-Tr)#Temperature at heater 5 in degree C\n",
"P5=0.2906#Pressure at heater 5 in MPa\n",
"t6=(t5-Tr)#Temperature at heater 6 in degree C\n",
"P6=0.108#Pressure at heater 6 in MPa\n",
"t7=(t6-Tr)#Temperature at heater 7 in degree C\n",
"P7=32.65#Pressure at heater 7 in kPa\n",
"\n",
"#Output\n",
"print \"The optimum pressure and temperature at different heaters are: \\n Heater 1: t1 = %3.1f degree C and p1 = %3.2f MPa\\n Heater 2: t2 = %3.1f degree C and p2 = %3.4f MPa\\n Heater 3: t3 = %3.1f degree C and p3 = %3.3f MPa\\n Heater 4: t4 = %3.1f degree C and p4 = %3.4f MPa\\n Heater 5: t5 = %3.1f degree C and p5 = %3.4f MPa\\n Heater 6: t6 = %3.1f degree C and p6 = %3.3f MPa\\n Heater 7: t7 = %3.1f degree C and p7 = %3.2f kPa\"%(t1,P1,t2,P2,t3,P3,t4,P4,t5,P5,t6,P6,t7,P7)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.4 Pg: 87"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"Percentage of total electricity generated which is consumed in running the auxiliaries is 7.32 percent\n"
]
}
],
"source": [
"#Input data\n",
"ng=0.97#Efficiency of electric generator \n",
"nt=0.95#Efficiency of turbine\n",
"nb=0.92#Efficiency of boiler\n",
"nc=0.42#Efficiency of cycle\n",
"no=0.33#Efficiency of overall plant\n",
"\n",
"#Calculations\n",
"na=(no/(ng*nt*nb*nc))#Efficiency of auxiliaries\n",
"n=(1-na)*100#Percentage of total electricity generated which is consumed in running the auxiliaries\n",
"\n",
"#Output\n",
"print \"Percentage of total electricity generated which is consumed in running the auxiliaries is %3.2f percent\"%(n)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.5 Pg: 87"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"Efficiency of steam generator is 91.54 percent \n",
"\n",
" Heat transfer per kg fuel in \n",
" (i)economiser is 5.3155 MJ/kg \n",
" (ii)boiler is 13.086 MJ/kg \n",
" (iii)superheater is 4.665 MJ/kg \n",
" (iv)air pre-heater is 3.392 MJ/kg \n",
"\n",
" Percentage of total heat absorption taking place in \n",
" (i)economiser is 23.04 percent \n",
" (ii)boiler is 56.73 percent \n",
" (iii)superheater is 20.23 percent\n"
]
}
],
"source": [
"#Input data\n",
"T1=140#Temperature with which feed water enters into economiser in degree C\n",
"T2=[25,250]#Temperature from air is preheated to in degree C\n",
"P1=60#Pressure with which steam leaves the drum in bar\n",
"x1=0.98#Dryness fraction\n",
"T3=450#Temperature with which steam leaves the superheater in degree C\n",
"cc=25.2#Calorific value of coal in MJ/kg\n",
"r=8.5#Rate of evaporation of steam per kg coal \n",
"wf=1#Mass of coal in kg\n",
"R=15#Air fuel ratio by mass\n",
"Cpa=1.005#Specific heat of air at constant pressure in kJ/kg.K\n",
"Cpw=4.2#Specific heat of water at constant pressure in kJ/kg.K\n",
"\n",
"#Calculations\n",
"h1=(T1*Cpw)#Enthalpy in kJ/kg\n",
"hf=1213.35#Enthalpy in kJ/kg\n",
"h2=hf#Enthalpy in kJ/kg\n",
"hfg=1571#Enthalpy in kJ/kg\n",
"h4=3301.8#Enthalpy in kJ/kg\n",
"h3=(hf+x1*hfg)#Enthalpy in kJ/kg\n",
"n=((r*(h4-h1))/(wf*cc*1000))*100#Efficiency\n",
"he=(r*(h2-h1))/wf*10**-3#Heat transfer in the economiser in MJ/kg\n",
"hb=(r*(h3-h2))/wf*10**-3#Heat transfer in the boiler in MJ/kg\n",
"hs=(r*(h4-h3))/wf*10**-3#Heat transfer in the superheater in MJ/kg\n",
"ha=(R*Cpa*(T2[1]-T2[0]))/wf*10**-3#Heat transfer in the air preheater in MJ/kg\n",
"pe=((h2-h1)/(h4-h1))*100#Percentage of total heat absorbed in the economiser in percent\n",
"pb=((h3-h2)/(h4-h1))*100#Percentage of total heat absorbed in the boiler in percent\n",
"ps=((h4-h3)/(h4-h1))*100#Percentage of total heat absorbed in the superheater in percent\n",
"\n",
"#Output\n",
"print \"Efficiency of steam generator is %3.2f percent \\n\\n Heat transfer per kg fuel in \\n (i)economiser is %3.4f MJ/kg \\n (ii)boiler is %3.3f MJ/kg \\n (iii)superheater is %3.3f MJ/kg \\n (iv)air pre-heater is %3.3f MJ/kg \\n\\n Percentage of total heat absorption taking place in \\n (i)economiser is %3.2f percent \\n (ii)boiler is %3.2f percent \\n (iii)superheater is %3.2f percent\"%(n,he,hb,hs,ha,pe,pb,ps)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.6 Pg: 88"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"(a) The cycle efficiency is 48.58 percent \n",
" (b) The feedwater temperature is 264 degree C \n",
" (c) The steam rate is 2.69 kJ/kWh \n",
" (d) The heat rate is 7411 kJ/kWh \n",
" (e) The quality of steam at turbine exhaust is 0.8932 \n",
" (f) The power output is 111.58 MW\n"
]
}
],
"source": [
"#Input data\n",
"p1=150#Pressure of inlet steam in bar\n",
"T1=550#Temperature of steam in degree C\n",
"p2=20#Pressure after expansion in bar\n",
"T2=500#Reheat temperature in degree C\n",
"pc=0.075#Condenser pressure in bar\n",
"php=50#Pressure of steam in h.p turbine in bar\n",
"pip=[10,5,3]#Pressure of steam in i.p turbines in bar\n",
"plp=1.5#Pressure of steam in l.p turbine in bar\n",
"m=300*1000#Steam flow rate in kg/h\n",
"\n",
"#Calculations\n",
"h1=3448.6#Enthalpy in kJ/kg\n",
"h4=3467.6#Enthalpy in kJ/kg\n",
"s1=6.5119#Entropy in kJ/kg.K\n",
"s2=s1#Entropy in kJ/kg.K\n",
"s3=s1#Entropy in kJ/kg.K\n",
"s4=7.4317#Entropy in kJ/kg.K\n",
"s5=s4#Entropy in kJ/kg.K\n",
"s6=s5#Entropy in kJ/kg.K\n",
"s7=s6#Entropy in kJ/kg.K\n",
"s8=s7#Entropy in kJ/kg.K\n",
"s9=s8#Entropy in kJ/kg.K\n",
"t2=370#Temperature in degree C\n",
"t3=245#Temperature in degree C\n",
"t5=400#Temperature in degree C\n",
"t6=300#Temperature in degree C\n",
"t7=225#Temperature in degree C\n",
"t8=160#Temperature in degree C\n",
"h2=3112#Enthalpy in kJ/kg\n",
"h3=2890#Enthalpy in kJ/kg\n",
"h5=3250#Enthalpy in kJ/kg\n",
"h6=3050#Enthalpy in kJ/kg\n",
"h7=2930#Enthalpy in kJ/kg\n",
"h8=2790#Enthalpy in kJ/kg\n",
"x9=(s9-0.5764)/7.6751#Dryness fraction\n",
"h9=168.79+x9*2406##Enthalpy in kJ/kg\n",
"h10=168.79#Enthalpy in kJ/kg\n",
"h11=h10+0.001*pip[1]*100#Enthalpy in kJ/kg\n",
"h12=467.11#Enthalpy in kJ/kg\n",
"t14=111.37#Temperature in degree C\n",
"h14=467#Enthalpy in kJ/kg\n",
"h13=h12#Enthalpy in kJ/kg\n",
"h14=h13#Enthalpy in kJ/kg\n",
"h15=h14#Enthalpy in kJ/kg\n",
"h16=561.47#Enthalpy in kJ/kg\n",
"h17=h16#Enthalpy in kJ/kg\n",
"h18=640.23#Enthalpy in kJ/kg\n",
"h19=h18+0.001*(p1-pip[1])*100#Enthalpy in kJ/kg\n",
"h20=762.8#Enthalpy in kJ/kg\n",
"h21=h20#Enthalpy in kJ/kg\n",
"h22=1154.23#Enthalpy in kJ/kg\n",
"h23=h22#Enthalpy in kJ/kg\n",
"m1=((h23-h21)/(h2-h22))#Mass in kg\n",
"m2=((h21-h19)-(m1*(h22-h20)))/(h5-h20)#Mass in kg\n",
"m3=(((1-m1-m2)*(h18-h17))-((m1+m2)*(h20-h18)))/(h6-h18+h18-h17)#Mass in kg\n",
"m4=((1-m1-m2-m3)*(h17-h15))/(h7-h16)#Mass in kg\n",
"m5=(((1-m1-m2-m3-m4)*(h14-h11))-(m4*(h16-h12)))/(h8-h12+h14-h11)#Mass in kg\n",
"WT=(h1-h2)+(1-m1)*(h2-h3)+(1-m1)*(h4-h5)+(1-m1-m2)*(h5-h6)+(1-m1-m2-m3)*(h6-h7)+(1-m1-m2-m3-m4)*(h7-h8)+(1-m1-m2-m3-m4-m5)*(h8-h9)#Workdone by turbine in kJ/kg\n",
"Wp=(0.5+14.5+0.15)#Workdone in kJ/kg\n",
"Wnet=(WT-Wp)#Net workdone in kJ/kg\n",
"Q1=(h1-h23)+(1-m1)*(h4-h3)#Heat supplied in kJ/kg\n",
"ncy=(Wnet/Q1)*100#Cycle efficiency in percent\n",
"t23=264#Temperature in degree C\n",
"sr=(3600/Wnet)#Steam rate in kJ/kWh\n",
"hr=((Q1/Wnet)*3600)#Heat rate in kJ/kWh\n",
"P=((Wnet*m)/3600)/10**3#Power output in MW\n",
"\n",
"#Output\n",
"print \"(a) The cycle efficiency is %3.2f percent \\n (b) The feedwater temperature is %d degree C \\n (c) The steam rate is %3.2f kJ/kWh \\n (d) The heat rate is %3.0f kJ/kWh \\n (e) The quality of steam at turbine exhaust is %3.4f \\n (f) The power output is %3.2f MW\"%(ncy,t23,sr,hr,x9,P)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.7 Pg: 92"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"The steam condition required at inlet of the turbine: \n",
" Enthalpy is 3085.3 kJ/kg \n",
" Entropy is 6.6192 kJ/kg.K \n",
" Pressure is 37.3 bar \n",
" Temperature is 344 degree C\n"
]
}
],
"source": [
"#Input data\n",
"m=10000#Mass flow rate of steam in kg/h\n",
"p=3#Pressure of steam in bar\n",
"P=1000#Power in kW\n",
"n=0.7#Internal efficiency of turbine\n",
"\n",
"#Calculations\n",
"dh=(P*3600)/m#Change in enthalpy in kJ/kg\n",
"h2=2725.3#Enthalpy in kJ/kg from Fig. E2.7 \n",
"h1=dh+h2#Enthalpy in kJ/kg \n",
"dh1h2s=dh/n#Change in enthalpy in kJ/kg\n",
"h2s=h1-dh1h2s#Enthalpy in kJ/kg\n",
"x2s=(h2s-561.47)/2163.8#Dryness fraction\n",
"s2s=1.6718+x2s*(6.999-1.6718)#Entropy in kJ/kg.K\n",
"s1=s2s#Entropy in kJ/kg.K\n",
"p1=37.3#Pressure in bar from Mollier diagram\n",
"t1=344#Temperature in degree C\n",
"\n",
"#Output\n",
"print \"The steam condition required at inlet of the turbine: \\n Enthalpy is %3.1f kJ/kg \\n Entropy is %3.4f kJ/kg.K \\n Pressure is %3.1f bar \\n Temperature is %d degree C\"%(h1,s1,p1,t1)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Ex: 2.8 Pg: 93"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {
"collapsed": false
},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"(a) the steam generation capacity of the bolier is 16.74 t/h \n",
" (b) the heat input to the boiler is 15113.7 kW \n",
" (c) the fuel burning rate of the bolier is 2.473 t/h \n",
" (d) the heat rejected to the condensor is 8369 kW \n",
" (e) the rate of flow of cooling water in the condensor is 0.333 m**3/s\n"
]
}
],
"source": [
"from __future__ import division\n",
"#Input data\n",
"Pl=5.6#Power load in MW\n",
"Hl=1.163#Heat load in MW\n",
"p1=40#Pressure in bar\n",
"T1=500+273#Temperature in K\n",
"p2=0.06#Pressure in bar\n",
"p3=2#Pressure in bar\n",
"CV=25#Calorific value in MJ/kg\n",
"n=88#Boiler efficiency in percent\n",
"T=6#Temperature rise in degree C\n",
"\n",
"#Calculations\n",
"h1=3445.3#Enthalpy in kJ/kg\n",
"s1=7.0901#Entropy in kJ/kg.K\n",
"s2=s1#Entropy in kJ/kg.K\n",
"s3=s1#Entropy in kJ/kg.K\n",
"x2=(s2-1.5301)/5.5970#Dryness fraction\n",
"h2=2706.7#Enthalpy in kJ/kg\n",
"h26=2201.9#Difference in enthalpy in kJ/kg\n",
"w=(Hl*10**3)/h26#Rate of steam extraction in kg/h\n",
"x3=(s1-0.52)/7.815#Dryness fraction\n",
"h3=(149.79+x3*2416)#Enthalpy in kJ/kg\n",
"h4=149.79#Enthalpy in kJ/kg\n",
"ws=((Pl*10**3+(w*(h2-h3)))/((h1-h2)+(h2-h3)))#Steam generation capacity in kg/s\n",
"ws1=(ws*3600)/1000#Steam generation capacity in t/h\n",
"h7=(504.7+(1.061*10**-3*(p1-p3)*100))#Enthalpy in kJ/kg\n",
"h5=(149.79+(1.006*100*p1*10**-3))#Enthalpy in kJ/kg\n",
"Q1=(((ws-w)*(h1-h5))+(w*(h1-h7)))#Heat input in kW\n",
"wf=((Q1/1000)/((n/100)*CV))*(3600/1000)#Fuel burning rate in t/h\n",
"Q2=((ws-w)*(h3-h4))#Heat rejected to the condensor in kW\n",
"wc=(Q2/(4.187*T))/1000#Rate of flow of cooling water in m**3/s\n",
"\n",
"#Output\n",
"print \"(a) the steam generation capacity of the bolier is %3.2f t/h \\n (b) the heat input to the boiler is %3.1f kW \\n (c) the fuel burning rate of the bolier is %3.3f t/h \\n (d) the heat rejected to the condensor is %3.0f kW \\n (e) the rate of flow of cooling water in the condensor is %3.3f m**3/s\"%(ws1,Q1,wf,Q2,wc)"
]
},
{
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"metadata": {},
"source": [
"## Ex: 2.9 Pg: 94"
]
},
{
"cell_type": "code",
"execution_count": 10,
"metadata": {
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"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"(a) the steam quality at the exhaust of the h.p turbine is 0.956 \n",
" (b) the power developed by the h.p turbine is 1154.62 kW \n",
" (c) the isentropic efficiency of the h.p turbine is 76.61 percent\n"
]
}
],
"source": [
"#Input data\n",
"m=21000#Steam rate in kg/h\n",
"p1=17#Pressure in bar\n",
"T1=230+273#Temperature in K\n",
"P=132.56#Power in kW\n",
"x2=0.957#Dryness fraction\n",
"p2=3.5#Pressure in bar\n",
"Pl=1337.5#Power in l.p turbine in kW\n",
"p3=0.3#Pressure in bar\n",
"x3=0.912#Dryness fraction\n",
"\n",
"#Calculations\n",
"h1=2869.7#Enthalpy in kJ/kg\n",
"s1=6.5408#Entropy in kJ/kg.K\n",
"h2=(870.44+x2*1924.7)#Enthalpy in kJ/kg\n",
"h3=h2#Enthalpy in kJ/kg\n",
"h56=(Pl*3600)/m#Difference in Enthalpy in kJ/kg\n",
"h6=(289.23+x3*2336.1)#Enthalpy in kJ/kg\n",
"h5=2649.04#Enthalpy in kJ/kg\n",
"s4s=s1#Entropy in kJ/kg.K\n",
"x4s=(s4s-1.7275)/5.2130#Dryness fraction\n",
"h4s=584.33+x4s*2148.1#Enthalpy in kJ/kg\n",
"w=(P/(h1-h2))#Flow rate in kg/s\n",
"ws=(m/3600)#Steam flow rate in kg/s\n",
"h4=((ws*h5)-(w*h3))/(ws-w)#Enthalpy in kJ/kg\n",
"x4=(h4-584.33)/2148.1#Dryness fraction\n",
"W=(ws-w)*(h1-h4)#Power developed by h.p turbine in kW\n",
"n=((h1-h4)/(h1-h4s))*100#Isentropic efficiency in percent\n",
"\n",
"#Output\n",
"print \"(a) the steam quality at the exhaust of the h.p turbine is %3.3f \\n (b) the power developed by the h.p turbine is %3.2f kW \\n (c) the isentropic efficiency of the h.p turbine is %3.2f percent\"%(x4,W,n)"
]
}
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