To obtain the masses and mass flows we convert gallons to ft3 and divide by the specific volume. These values are entered on the table. The final state mass is given by conservation of mass or Then the heat transfer rate becomes 6. The gas then undergoes a polytropic expansion with a polytropic exponent of 1.15 to 0.3 liters. Compare the work performed in kJ for air as the gas versus hydrogen as the gas.
Italicized values are from ideal gas relations.
Bold values are calculated. At state 2 we can determine the pressure from the polytropic relation. The boundary work is then given by Since the calculation above never used the fact that air was our ideal gas, we will obtain the same boundary work for hydrogen as the gas. In an open feedwater, subcooled liquid water is heated to saturated liquid by mixing directly with steam. Bold values are calculated.