Experimental study on the performance of an improved dehumidification system integrated with precooling and recirculated regenerative rotary desiccant wheel

Abstract

High temperature and humidity conditions in enclosed cabins pose a threat to the safety of staff and equipment, and will result in intensive energy consumption by conventional air conditioning dehumidification systems. Therefore, an improved dehumidification system integrated with precooling and recirculated regenerative rotary desiccant wheel was proposed. The effects of the process air parameters (temperature and humidity), precooling temperature and regeneration air parameters (temperature and flow ratio) were experimentally investigated. Key performance indicators were analyzed, including the moisture removal capacity (MRC), thermal coefficient of performance (COPth), sensible energy ratio (Es) and dehumidification coefficient of performance (DCOP). The MRCtot was found to be improved by 29.7% at most compared with that of a conventional chilled water cooling system. In particular, the optimal MRC was obtained by an appropriate ratio between the regeneration and process airflows. The optimal ratio was determined between 8% and 20%. The DCOP and Es of the rotary desiccant wheel decreased with increasing regeneration airflow ratio. Moreover, COPth ranged from 0.33 to 1.17, and was improved with increasing process air temperature/humidity and decreasing precooling temperature. Overall, the feasibility of the system was verified and dehumidification characteristics under various working conditions were demonstrated to prompt its application.