Saturated steam at 1 atm and 100°C is continuously generated from liquid water at 1 atm and 25°C by thermal contact with hot air in a counterflow heat exchanger. The air flows steadily at 1 atm. Determine values for m (steam)/ri (air) for two cases:
a) Air enters the exchanger at 100°C.
b) Air enters the exchanger at 500°C.
For both cases, assume a minimum approach T for heat exchange of 10°C.