Experimental study on the effect of high humidity on the heat storage of phase change plate under forced convection

The integration of phase change materials (PCMs) with building structures or environmental control systems can enhance thermal comfort and energy efficiency. Phase change units are used for cooling and dehumidification in high-humidity situations, but the involved heat and mass transfer processes remain inadequately understood, especially when forced convection is included. To fill this gap, this study establishes an experimental platform characterized by a high-humidity environment with forced convection for phase change plate (PCP) to investigate the interaction between the surface condensation and the heat storage process of the PCP. It explores the impact of different airflow parameters on the heat storage process of PCP, derives correlation equations related to heat and mass transfer criteria, and finally derives an equivalent heat transfer coefficient equation. Experimental results indicate that increasing supply air temperature, relative humidity, and air velocity promote heat transfer between moist air and PCP, while the latent heat transfer shows the significant improvement. At a relative humidity of 95 %, the average latent heat transfer rate constitutes 75.2 % of the total average heat transfer rate, and the duration of phase change is shortened by 57.0 %. However, the impact on sensible heat transfer is limited and different. The criterion equations for heat transfer and mass transfer follow the same form. The equivalent heat transfer coefficient hequal is negatively correlated with temperature difference, and positively correlated with humidity ratio difference and air velocity. This study provides valuable insights for the design of phase change cooling and dehumidifying systems in high-humidity environments.