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What is the value of Latent heat transfer in a process of humidification having hfg = 10 kJ / kg of dry air, W1 = 0.0071 kJ / kg of dry air and W2 = 0.0017 kJ / kg of dry air?

What is the value of Latent heat transfer in a process of humidification having hfg = 10 kJ / kg of dry air, W1 = 0.0071 kJ / kg of dry air and W2 = 0.0017 kJ / kg of dry air? Correct Answer 0.054

Latent heat transfer i.e., LH = (h2 – h1) = hfg (W2 – W1) denotes Humidification. As, in the humidification process there is an increase in specific humidity so W2 > W1 and also increase in enthalpy, h2 > h1. So, latent heat transfer = hfg (W2 – W1) = 10 (0.0071 – 0.0017) = 0.054 kJ / kg of dry air.

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