In: Mechanical Engineering
The capacity of a propane vapor-compression refrigeration system is 8 tons. Saturated vapor at 0°F enters the compressor, and superheated vapor leaves at 120°F, 180 lbf/in.2 Heat transfer from the compressor to its surroundings occurs at a rate of 3.5 Btu per lb of refrigerant passing through the compressor. Liquid refrigerant enters the expansion valve at 85°F, 180 lbf/in.2 The condenser is water-cooled, with water entering at 65°F and leaving at 80°F with a negligible change in pressure. Determine
(a) the compressor power input, in Btu/min |
(b) the mass flow rate of cooling water through the condenser, in lb/min |
(c) the coefficient of performance |
Round answers to 3 significant digits.