Engineering Board Exam Reviewer · Thermodynamics · medium
A boiler produces 10 kg/s of steam, with an enthalpy rise of 2500 kJ/kg. It burns 0.8 kg/s of fuel with a heating value of 40,000 kJ/kg. What is the boiler efficiency?
- 78.13%
- 6.25%
- 21.88%
- 62.50%
Answer
A. 78.13%
Solution
b = ms h / (mf HV) = 10(2500)/[0.8(40,000)] = 25,000/32,000 = 78.13%.
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