A fuel is burned during a steady-flow combustion process. Heat is lost to the surroundings at 280 K at a rate of 920 kW. The entropy of the reactants entering per unit time is 14 kW/K and that of the products is 12 kW/K. The total rate of exergy destruction during this combustion process is

Question

Quizplus · Accepted Answer

Solved by EES Software. Solutions can be verified by copying-and-pasting the following lines on a blank EES screen. 
To=280 "K"
Q_out=920 "kW"
S_react=14 "kW'K"
S_prod= 12 "kW/K"
S_react-S_prod-Q_out/To+S_gen=0 "Entropy balance for steady state operation, Sin-Sout+Sgen=0"
X_dest=To*S_gen
"Some Wrong Solutions with Common Mistakes:"
W1_Xdest=S_gen "Taking Sgen as exergy destruction" 
W2_Xdest=To*S_gen1; S_react-S_prod-S_gen1=0 "Ignoring Q_out/To"

A Fuel Is Burned During a Steady-Flow Combustion Process