Exergy Analysis of an Air Dehumidification System Equipped with Mixing Box and Heat Exchanger Heat Recovery Units

Abstract

Exergy analysis emboldens in cases that all the inefficiencies and bottlenecks to improve energy systems are to be addressed. In this study, a novel vapor compression air dehumidifier integrated with an auxiliary heat exchanger in series arrangement with the main condenser in order to mitigate the reheat coil, and an extra mixing box to recover the ventilated air heat has been introduced. A comprehensive methodology for exergetic analysis of vapor compression heating ventilation and air conditioning systems has been presented. The quasi-dynamic component-by-component exergy analyses of both the conventional and novel air dehumidification systems have been conducted for a specific outside air fraction. Also, sensitivity analyses have been conducted on the exergy destruction and efficiency as a function of outside air fraction. Results denote that for the outside air fraction of 53%, exergy destruction of the novel air dehumidification system has decreases up to 32.4% and exergy efficiency has ramped up by 53.45%. Moreover, by rising the outside air fraction from none to 100%, exergy destruction in the novel air dehumidification system has declined by 46% to 30.5 %, and exergy efficiency has undergone a 106% to 40.3 % increase compared with the conventional system depending on the outside.