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// Given:-
EfFdot = 100.00 // exergy rate of fuel entering the boiler in MW
cF = 1.44 // unit cost of fuel in cents per kw.h
Zbdot = 1080.00 // the cost of owning and operating boiler in dollars per hour
Ef1dot = 35.00 // exergy rate of exiting steam from the boiler in MW
p1 = 50.00 // pressure of exiting steam from the boiler in bar
T1 = 466.00 // temperature of exiting steam from the boiler in degree celcius
Ztdot = 92.00 // the cost of owning and operating turbine in dollars per hour
p2 = 5.00 // pressure of exiting steam from the turbine in bars
T2 = 205.00 // temperature of exiting steam from the turbine in degree celcius
m2dot = 26.15 // mass flow rate of exiting steam from the turbine in kg/s
T0 = 298.00 // in kelvin
// Part(a)
// From table A-4,
h1 = 3353.54 // in kj/kg
h2 = 2865.96 // in kj/kg
s1 = 6.8773 // in kj/kg.k
s2 = 7.0806 // in kj/kg.k
// Calculations
// From assumption,For each control volume,Qcvdot = 0 and kinetic and potential energy effects are negligible,the mass and energy rate
// balances for a control volume enclosing the turbine reduce at steady state to give
Wedot = m2dot *(h1-h2)/1000 // power in MW
Ef2dot = Ef1dot+m2dot*(h2-h1-T0*(s2-s1))/1000 // the rate exergy exits with the steam in MW
// Results
printf( ' For the turbine,the power is %.2f MW.',Wedot)
printf( ' For the turbine,the rate exergy exits with the steam is %.2f MW.',Ef2dot)
// Part(b)
// Calculations
c1 = cF*(EfFdot/Ef1dot) + ((Zbdot/Ef1dot)/10**3)*100 // unit cost of exiting steam from boiler in cents/Kw.h
c2 = c1 // Assigning the same unit cost to the steam entering and exiting the turbine
ce = c1*((Ef1dot-Ef2dot)/Wedot) + ((Ztdot/Wedot)/10**3)*100 // unit cost of power in cents/kw.h
// Results
printf('The unit costs of the steam exiting the boiler of exergy is: %.2f cents per kw.h.',c1)
printf('The unit costs of the steam exiting the turbine of exergy is: %.2f cents per kw.h.',c2)
printf('Unit cost of power is: %f cents per kw.h.',ce)
// Part(c)
C2dot = (c2*Ef2dot*10**3)/100 // cost rate for low-pressure steam in dollars per hour
Cedot = (ce*Wedot*10**3)/100 // cost rate for power in dollars per hour
// Results
printf( ' The cost rate of the steam exiting the turbine is: %.2f dollars per hour.',C2dot)
printf( ' The cost rate of the power is: %.2f dollars per hour.',Cedot)
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