Design and evaluation of metal foam horizontal tube-and-shell phase change accumulator: Optimal position distribution of heating tubes

Recently, the combination of phase change materials and metal foams shows great potential in latent heat storage applications. In order to improve heat storage efficiency, this study utilizes experimental and numerical simulation techniques to establish a symmetric two-dimensional model and employs response surface method to optimize heat source location distribution within a three-tube heat accumulator. The research findings indicate that the optimal model of the three-tube accumulator filled with paraffin-metal foam reduces the full melting time to 2020 s, which is 49.75 % shorter than that of the single-tube accumulator filled with paraffin-metal foam. In addition, compared with pure paraffin, the optimal model filled with paraffin-metal foam can reduce the full melting time by 4860 s (about 70.64%), which means that metal foam can effectively enhance the heat transfer of PCM. Furthermore, we explore the influence of pore parameters on PCM heat transfer. It is demonstrated that metal foam with a porosity of 0.90 decreases the full melting time of the three-tube heat accumulator by 1110 s (about 38.81%) compared to the porosity of 0.99, and metal foam with pore density of 10 PPI reduces it by 1280 s (about 38.79%) compared to the pore density of 100 PPI.