Determine the total entropy production rate for the heat exchanger shown in Figure.
In addition to the air-water heat transfer within the heat exchanger, the air also loses an unknown amount of heat to the surroundings while the water receives an additional 10.0 Btu/s from the surroundings.
Assume the internal air-water interface is isothermal at 100.°F and the outer surface of the heat exchanger is isothermal at 70.0°F. Neglect all flow stream pressure losses.
