Chapter 8, Problem 8.57P

Consider a heat transfer process of the steady form that occurs along a plain wall. While the inner room temperature was kept at 25 °C, the outdoor environment temperature was measured to be 2 °C. If the heat transfer at this plain wall in an hour is 3,528 kJ, determine the.total exergy destruction per unit time (the rate), which occurs during this heat transfer process, a) use the total entropy generation to find the rate of the total exergy destruction in the room (i.e.., use the entropy balance), b) use the exergy balance to find the rate of the total exergy destruction in the room

A fraction of some power to a motor (1), 2 kW, is turned into heat transfer at 500 K (2) and then it dissipates in the ambient at 300 K (3). Give the rates of exergy along the process 1-2-3.

Air is heated at constant pressure from 2 7 degrees C to 57 degrees C at 3 bar in a heater from an infinite heat source at temperature 227 degrees C Find the gain in availability of air and the effectiveness of the heater. Assume To = 280K and Cp =1.0 kj/kgK.