Experimental Comparison of Indirect Evaporative Coolers: Typical Cross-flow and Regenerative Types

Abstract

The main purpose of this paper is to propose an indirect evaporative cooler (IEC) with the secondary air flowing though the wet channels in U-shape. The proposed IEC operated in three different operation modes; that is, typical mode, regenerative mode with the outdoor air used as scavenger air, and regenerative mode with the return air used as secondary air. The performance of the IEC in each operation mode was determined by the tests performed in an environmental chamber with varying the inlet primary air condition, airflow rate, and the working-to-primary air ratio. The performances of proposed IECs were compared by performance evaluation indices: supply air temperature, wet bulb effectiveness, temperature drop, cooling capacity, pressure drop, and coefficient of performance (COP). As results, typical cross flow type IEC showed the lowest supply air temperature and highest COP under humid, dry and dehumidified condition.