TYPES OF EXERGETIC LOSSES IN EXHAUST GAS HEAT UTILIZERS

The paper presents the results of a study of exergetic losses of various types for individual modules of exhaust gas heat recovery units. The relative contribution to the total exergy losses in heat recovery plants of exergetic losses associated with nonequilibrium heat exchange between flue gases and wall, between wall and water or air, losses due to thermal conductivity and due to the movement of heat carriers is analyzed. Data for four types of exhaust heat recovery units are given. It is pointed out that the relative contribution of exergy losses due to heat transfer from the flue gases to the wall is approximately the same for all types of heat recovery units and significantly exceeds the contribution of exergy losses of other types.