Experimental and numerical analysis on total heat recovery performance of an enthalpy wheel under high temperature high humidity working conditions

Abstract

Enthalpy wheels (EWs) have been extensively used for total heat recovery from ventilation air. Despite there being many studies reporting on their performances under common working conditions with a small temperature and humidity ratio difference (ΔT < 20 °C, Δω < 15 g kg−1), there are few studies reporting on their performances under high temperature high humidity (HTHH) working conditions. This study aims to investigate the total heat recovery performance of an EW under HTHH working conditions. A mathematical model is established and validated to predict the performance. The effects of rotation speed, air inlet velocity, air inlet temperature, and air inlet humidity ratio on the total heat recovery performance are numericallyinvestigated, and performance comparisons between HTHH working conditions and other common working conditions are also carried out. The comparison results show that the EW performs better for total heat recovery under HTHH working conditions, with εtotal improving by 6% compared to common working conditions. The reasons behind the discrepancies are revealed by analyzing the distributions of temperature and humidity in the EW. This study is expected to be beneficial to design EWs to recover total heat from HTHH waste gas.