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In: Mechanical Engineering

Moist air at 55 oF dry bulb temperature and 40% relative humidity is first heated through...

Moist air at 55 oF dry bulb temperature and 40% relative humidity is first heated through a heating coil. The air is then adiabatically humidified by saturated water vapor at 4.5 psia. The exit air has a dry bulb temperature of 90 oF and wet bulb temperature 65 oF. Air is supplied at a volume flow rate of 478.5 cfm. Assume sea level pressure throughout. Determine the following.

a) Show the inlet and outlet air condition clearly on the psychrometric chart clearly marking them as 1 and 2 respectively.

b) Show the sensible heating process and humidification process on the psychrometric chart clearly marking them. Draw the overall process line.

c) Calculate the heat transfer rate of the heating coil. Show your calculation.

d) Calculate the mass flow rate of the water vapor. Show your calculation.

e) What is the SHF value? Show clearly how you obtained it.

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