Cooling performance of a thermal energy storage-based portable box for cold chain applications

Cooling performance of a portable box integrating with phase change material (PCM)-based cold thermal energy storage (TES) modules was studied and reported in this paper. The effects of locations of the PCM modules, melting point of the PCM, and insulation materials on the cooling duration of the box were numerically investigated with an experimentally validated model. Five configurations of PCM modules inside the box were examined: Case 1 - 100 % of the PCM located at the top; Case 2 - 20 % at the top and 20 % on each of side walls; Case 3 - 25 % on each of the side walls; Case 4 - 20 % on each of the side walls and 20 % at the bottom; and Case 5 - 100 % at the bottom. Five different PCMs with melting points at 2 degrees C, 3 degrees C, 4 degrees C, 5 degrees C and 8 degrees C were considered. A comparison was made between two different insulation materials (polyurethane, vacuum insulated panels) on the cooling performance. It was found that the configuration of PCM modules, the PCM melting point, and the type of insulation material all affected the cooling durations. The configuration of PCM with 20 % located at the top and 20 % on each of the side walls, with the melting point at 2 degrees C and the vacuum insulated panel (VIP) gave the longest duration time. The maximum cooling time was up to 46.5 h with the maximum discharging efficiency at 90.7 % and the highest discharging depth at 99.4 %, offering a great potnetial for cold chain applications.