Heat transfer and fluid flow in a PCM-filled enclosure: Effect of inclination angle and mid-separation fin

This paper presents a numerical study on the thermal behavior within a phase change material PCM (Rubitherm GmbH; RT-27) filling up a rectangular capsule, with and without adding a mid-separating fin with varying the inclination angle (0°, 45°, and 90°). To solve the governing equations, the Finite Elements Method-based commercial software; COMSOL-MULTIPHYSICS is employed. The results prove that the melting and storing energy rate got faster with the variation of the capsule's inclination angle from 90°, 45° then 0°. Moreover, adding a fin decreased the melting time by 1.28%, 12.82% and 20.52% for the cases 90°, 45°, and 0° respectively. It is worthy to note that the rate of storing thermal energy would be accelerated by 14.75% when the inclination angle is equal to 90°, 19.67% for 45° and 36.88% for 0°. By consequence, the best choice selected by the end of this work is for a horizontal fin with an inclinaition angle equal to 0°.