Simulation of a composite latent heat storage tank with horizontal baffles and two phase-change temperatures

A composite latent heat storage tank (CLHST) is fabricated using baffles and two phase-change materials (PCMs) with different phase-change temperatures. The performance of the tank is optimized based on both structure and material. This optimization approach is a new integrated method differing from those developed in previous studies, where only a single aspect of the structure/material is considered. Experimental verification and simulation analysis are used to analyze the difference between the integrated and single-structure/material optimization methods and their influence on the thermal properties of the traditional latent heat storage tank (TLHST). The results show that the CLHST exhibits the best characteristics. Compared with the TLHST, the CLHST's charging quantity increases by 13.6%, the outlet temperature can be increased by 6.5°C, and the utilization rate of PCM exceeds 85%. Moreover, the PCM in the CLHST melts more completely than unilaterally adding baffles. The charging and discharging quantities of the CLHST increase by more than 10% than just using two PCMs. Furthermore, adding baffles can increase the charging quantity by 11% compared to using two PCMs. Evidently, the tank design must be improved considering several aspects, and structural optimization plays a more important role in improving tank performance.