Inclination Angles on the Thermal Behavior of Phase-Change Material (PCM) in a Cavity Filled with Copper Foam Partly

Abstract In this study, the influence of the inclination angle was analyzed on the thermal behavior of PCM in the cavity filled with copper foam fins. Twelve inclination angles from 0° to 360° were studied for the thermal storage unit, while the two-temperature equation thermal transfer model was built. The liquid fraction, the temperature response rate, and the average heat flow were employed as evaluation parameters. Numerical results displayed the inclination angle had the great influence on the PCM thermal performance and by optimizing the inclination angle, the whole phase-change time was shortened by 43.16% with the inclination angle from 0o to 180o. In melting and freezing processes, the inclination angle had the opposite rules and affected the thermal performance difference obviously. With the inclination angle from 0o to 180o, the difference values were reduced from 17904s, 712 w/m2 and 0.00867°C/s to 1709s, 31 w/m2 and 0.00051°C/s for full phase-change time, the average heat flow and temperature response rate, respectively. And the optimum inclination angle was 180o in the view of a melting and freezing period and the reasonable inclination angle could be selected according to thermal storage and release rules in the engineering application.