Hollowed and Perforated Fins in Latent Heat Storage Units for High-Temperature Hybrid Thermal Energy Storage Applications

Abstract

High-temperature thermal energy storage (TES) is essential for next-generation concentrated solar power (CSP) plants in order to ensure continuous energy supply. Hybridization of latent heat storage (LHS) and sensible heat storage (SHS) enhances energy density, thermal stability, and efficiency by leveraging the high storage capacity of phase change materials (PCMs) while reducing thermal ratcheting for sensible storage. This study focuses on a numerical analysis of a shell-and-tube LHS using sodium as heat transfer fluid (HTF). It examines the impact of hollowed and perforated fins to enhance effective heat exchange. Simulations were conducted in a 3D solution domain using ANSYS Fluent. The results show that fin removal rate and hole placement are crucial design factors. A 20% perforation rate in the Perforated fin-Middle(full) configuration maintains high heat transfer efficiency, reduces material costs, and increases PCM storage. In comparison to molten salts as HTFs, liquid metals exhibit effectively lower HTF outlet temperatures, which is vital for LHS-SHS integration. These findings provide valuable insights for optimizing high-temperature TES units in large-scale CSP applications.