In a constant pressure process steam is generated from 10 bar and 0.8 dry condition till it become dry and saturated. Determine amount of heat added per kg of steam. From steam table at 10 bar Tsat = 179.9°C hf = 762.6 kl/kg, hg = 2776.2 kJ/kg 

1 Answer

Answer :

Constant pressure process

Final condition of steam is dry saturated

Enthalpy of dry steam = hg= hf + hfg =2776.2 KJ/Kg ….Given

Latent heat of vaporization = hfg = hg – hf =2776.2-762.6 =2013.6 KJ/Kg

Initial condition of steam is 0.8 dry

Enthalpy of wet steam = hw= hf + x. hfg = 762.6+0.8 X 2013.6 =2373.48 KJ/Kg

Heat added = hg-hw = 402.72 KJ/kg

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