Question

Lower calorific value can be determined by equation:

(a) LCV = HCV – m*2466

(b) LCV = HCV + (m/2466)

(c) LCV = HCV – (m/2466)

(d) LCV = HCV + (m*2466)

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This question is from Calorific Value of Fuels in section Steam Power Plant of Energy Engineering

Answer 1

Right answer is (a) LCV = HCV – m*2466

Easy explanation: Lower calorific value can be determined equation [LCV = HCV – m*2466]. The latent heat lost to the atmosphere depends on evaporation pressure and the amount of water vapors formed. Due to difficulty in measuring the evaporation pressure, it is assumed that evaporation takes place at a saturation temperature of 15°C. The latent heat corresponding to this saturation is 2466 kl/kg.

                                    m = mass of water vapour formed per kg of fuel burnt.