Engineering Board Exam Reviewer · Thermodynamics · medium
In an ideal Rankine cycle, the turbine inlet enthalpy is 3200 kJ/kg, turbine exit enthalpy is 2200 kJ/kg, the pump inlet enthalpy is 192 kJ/kg and pump work is 8 kJ/kg. What is the thermal efficiency?
- 33.07%
- 31.25%
- 33.24%
- 31.00%
Answer
A. 33.07%
Solution
wnet = (3200 - 2200) - 8 = 992 kJ/kg. q in = 3200 - (192 + 8) = 3000 kJ/kg. = 992/3000 = 33.07%.
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