Effect of thermal performance on melting and solidification of lauric acid PCM in cylindrical thermal energy storage

Abstract

In this experimental study, a designed vertical shell and tube type thermal energy storage system, with the effect of natural convection during melting and solidification process is investigated. The temperature variation at different positions both in axial and radial locations are measured during melting and solidification process of lauric acid PCM. Results revealed that 0.4 kg of lauric acid PCM required the time of 4800 seconds for completion of the melting process (i.e., liquid fraction=1) within the predicted designed cylindrical thermal energy storage system. Fourier number, Rayleigh number, and Nussult number justified that natural convection occurs in the designed thermal energy storage system. Due to 7.91% increment in the thermal gradient, energy storage rate is greater 8.012% at axial height 0.0846m than the axial height 0.0423m. It also observed, after 4800 seconds heat transfer rate decreases gradually and within the time range of 4200-5400 seconds, it is decreased with 6.72%.