Exergy Analysis Of An Air Conditioning Process

The exergy analysis of an air conditioning process in wintertime is presented in this paper. This process consists of mixing outdoor air with conditioned air, heating, humidifying, and reheating the air mixture. The air is heated in the heat exchangers by warm water at a temperature of 80/60 degrees C and humidified by spraying water at a temperature of 12 degrees C. The ratio of the mass flow rates of outdoor and conditioned air is varied, and it is upon this variable that the exergy analysis is performed. The five cases are analyzed with different outdoor air temperature values. It is shown that the heat transfer rate in the heat exchangers is the smallest at the ratio of mass flow rates of outdoor and conditioned air g(1) = 0.45. The greatest exergy destruction is apparent in the heat exchangers, and the maximum exergy efficiency of the whole process epsilon(ex) = 0.71 is achieved at the ratio g(1) = 0.45. According to the exergy criterion, this air conditioning is a relatively efficient process.