FINITE-ELEMENT ANALYSIS OF A MULTISTAGE LATENT-HEAT THERMAL STORAGE-SYSTEM

A new thermal storage system using multiple phase change materials (PC Ms) is developed. It consists of several shell-and-tube thermal storag e exchangers, which are connected in series to improve the system effi ciency. Each exchanger uses a different PCM To reach optimal system ef ficiency, the melting points of the PCMs are carefully selected accord ing to a thermodynamic optimization analysis. A finite element model i s developed to simulate the cyclic thermal process in the multi-exchan ger system. Computations were carried out for a three-exchanger system to investigate the advantages of the multiple-PCM system over the con ventional single-PCM system. Simulation results were compared and foun d to be in good agreement with the results of a thermodynamic optimiza tion analysis.