Question

Air flowing through a duct is heated through contact with a heat exchanger through which steam is flowing. Dry air enters one inlet of the heat exchanger at 70 F and 13.7 psia with a volume flow rate of 2000 ft3 /min. Saturated steam at 15 psig enters the other heat exchanger inlet and exits with 15% quality. Determine the heat transfer rate (Btu/hr) and mass flow rate of steam (lbm/hr) necessary to provide an air outlet temperature of 140 F.

Answer 1