initial commit / add all books

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+// Display mode

+mode(0);

+// Display warning for floating point exception

+ieee(1);

+clear;

+clc;

+disp("Engineering Thermodynamics by Onkar Singh Chapter 8 Example 9")

+P=15*10^3;//turbine output in KW

+disp("At inlet to first turbine stage,h2=3230.9 KJ/kg,s2=6.9212 KJ/kg K")

+h2=3230.9;

+s2=6.9212;

+disp("For ideal expansion process,s2=s3")

+s3=s2;

+disp("By interpolation,T3=190.97 degree celcius from superheated steam tables at 6 bar,h3=2829.63 KJ/kg")

+T3=190.97;

+h3=2829.63;

+disp("actual stste at exit of first stage,h3_a=h2-0.8*(h2-h3) in KJ/kg")

+h3_a=h2-0.8*(h2-h3)

+disp("actual state 3_a shall be at 232.78 degree celcius,6 bar,so s3_a=7.1075 KJ/kg K")

+s3_a=7.1075;

+disp("for second stage,s3_a=s4;By interpolation,s4=7.1075=sf at 1 bar+x4*sfg at 1 bar")

+s4=7.1075;

+disp("from steam tables,at 1 bar,sf=1.3026 KJ/kg K,sfg=6.0568 KJ/kg K")

+sf=1.3026;

+sfg=6.0568;

+disp("so x4=(s4-sf)/sfg")

+x4=(s4-sf)/sfg

+x4=0.958;//approx.

+disp("h4=hf at 1 bar+x4*hfg at 1 bar in KJ/kg")

+disp("from steam tables,at 1 bar,hf=417.46 KJ/kg,hfg=2258.0 KJ/kg")

+hf=417.46;

+hfg=2258.0;

+h4=hf+x4*hfg

+disp("actual enthalpy at exit from second stage,h4_a=h3_a-.8*(h3_a-h4) in KJ/kg")

+h4_a=h3_a-.8*(h3_a-h4)

+disp("actual dryness fraction,x4_a=>h4_a=hf at 1 bar+x4_a*hfg at 1 bar")

+disp("so x4_a=(h4_a-hf)/hfg")

+x4_a=(h4_a-hf)/hfg

+disp("x4_a=0.987,actual entropy,s4_a=7.2806 KJ/kg K")

+s4_a=7.2806;

+disp("for third stage,s4_a=7.2806=sf at 0.075 bar+x5*sfg at 0.075 bar")

+disp("from steam tables,at 0.075 bar,sf=0.5764 KJ/kg K,sfg=7.6750 KJ/kg K")

+sf=0.5764;

+sfg=7.6750;

+disp("so x5=(s4_a-sf)/sfg")

+x5=(s4_a-sf)/sfg

+x5=0.8735;//approx.

+disp("h5=2270.43 KJ/kg")

+h5=2270.43;

+disp("actual enthalpy at exit from third stage,h5_a=h4_a-0.8*(h4_a-h5)in KJ/kg")

+h5_a=h4_a-0.8*(h4_a-h5)

+disp("Let mass of steam bled out be m1 and m2 kg at 6 bar,1 bar respectively.")

+disp("By heat balance on first closed feed water heater,(see schematic arrangement)")

+disp("h11=hf at 6 bar=670.56 KJ")

+h11=670.56;

+disp("m1*h3_a+h10=m1*h11+4.18*150")

+disp("(m1*2829.63)+h10=(m1*670.56)+627")

+disp("h10+2159.07*m1=627")

+disp("By heat balance on second closed feed water heater,(see schematic arrangement)")

+disp("h7=hf at 1 bar=417.46 KJ/kg")

+h7=417.46;

+disp("m2*h4+(1-m1-m2)*4.18*38=(m1+m2)*h7+4.18*95*(1-m1-m2)")

+disp("m2*2646.4+(1-m1-m2)*158.84=((m1+m2)*417.46)+(397.1*(1-m1-m2))")

+disp("m2*2467.27-m1*179.2-238.26=0")

+disp("heat balance at point of mixing,")

+disp("h10=(m1+m2)*h8+(1-m1-m2)*4.18*95")

+disp("neglecting pump work,h7=h8")

+disp("h10=m2*417.46+(1-m1-m2)*397.1")

+disp("substituting h10 and solving we get,m1=0.1293 kg and m2=0.1059 kg/kg of steam generated")

+m1=0.1293;

+m2=0.1059;

+disp("Turbine output per kg of steam generated,Wt=(h2-h3_a)+(1-m1)*(h3_a-h4_a)+(1-m1-m2)*(h4_a-h5_a)in KJ/kg of steam generated")

+Wt=(h2-h3_a)+(1-m1)*(h3_a-h4_a)+(1-m1-m2)*(h4_a-h5_a)

+disp("Rate of steam generation required=P/Wt in kg/s")

+P/Wt

+disp("in kg/hr")

+P*3600/Wt

+disp("capacity of drain pump i.e. FP shown in layout=(m1+m2)*69192 in kg/hr")

+(m1+m2)*69192

+disp("so capacity of drain pump=16273.96 kg/hr")

+

+

+

diff --git a/2873/CH8/EX8.9/Ex8_9_1.jpg b/2873/CH8/EX8.9/Ex8_9_1.jpg
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diff --git a/2873/CH8/EX8.9/Ex8_9_2.jpg b/2873/CH8/EX8.9/Ex8_9_2.jpg
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