Assignment:
Refrigerant 134a enters a heat exchanger in a steady state refrigeration system as saturated vapor at 0 °F and exits at 20 °F with no change in pressure. A separate liquid stream of Refrigerant 134a passes in counterflow to the vapor stream, entering at 105 °F, 160 psia and exiting at a lower temperature while experiencing no pressure drop. The outside of the heat exchanger is well insulated, and the streams have equal mass flow rates. Neglecting kinetic and potential energy effects, determine the exit temperature of the liquid stream in degrees F.