Liquid-structure coupled simulation study on impacts of HTF temperature on discharge and mechanics performances of PCM heat storage system

Abstract

This paper presents an influence estimate of typical factors on heat release and mechanics performances of the latent thermal energy storage (LTES) tank with phase change material (PCM) by using the liquid-structure coupled calculation approach. Two heat transfer material temperatures are evaluated, including the cold molten salt temperature (MST) and hot MST. The results demonstrate that when the cold MST decreases from 610 K to 530 K, the HR duration will be reduced, the total heat release quantity (HRQ) increases, the average heat release power (HRP) increases from 3.22 MW to 7.98 MW, but the peak maximum mechanical stress (MMS) of the tank wall also rises. As the hot MST rises from 730 K to 810 K, the HRQ increases obviously, the average HRP increases from 5.09 MW to 6.63 MW, but the peak MMS also increases to 159.6 MPa. Hence, to improve the HR performance of the LTES system, under the condition of ensuring the structural safety of the LTES system, the hot MST should appropriately be increased, and the cold MST should be decreased properly.