Performance analysis of a counter-flow indirect evaporative cooling system

A counter-flow regenerative indirect evaporative heat exchanger (RIEHX) was introduced and investigated. This paper aims to conduct an experimental study for the RIEHX to investigate the cooling performance under different operating conditions. The experimental prototype was able to adjust the inlet air flow rate and temperature. The thermal performance of the RIEHX was tested with variable inlet conditions. The experimental results have demonstrated that the supply air can be effectively cooled along the product air flow passages by transferring heat to the wet side of the RIEHX due to water evaporation. Under a constant inlet air velocity, the product air with a higher inlet temperature can obtain a larger temperature reduction. In addition, a lower air flow rate may enhance the cooling effect due to the increased contact duration between the air streams. The proposed system is able to improve the cooling effectiveness of the conventional plate-type indirect evaporative cooler.