Enhancing a Double Pipe PCM Reservoir Melting Efficiency Through Innovative Fin Arrangements: A Numerical Study

This study explores the enhancement of phase change material (PCM) melting within a double-pipe reservoir by optimizing the fins’ shape and location. Traditional designs with uniformly distributed fins become less effective when certain areas of the PCM have fully melted while other regions remain solid. To overcome this limitation, we developed and tested five progressively refined fin layouts, resulting in 13 distinct cases and a base case. Each layout was designed to maintain consistent PCM volume while strategically placing fins in less active regions, which were identified through iterative analysis and insights from previously analyzed layouts. Three less active regions in the heat exchanger—at 0, 90, and 180 degrees—were identified, and the fins were placed or extended to these areas. The most effective configuration, Layout 5, significantly improved energy distribution and reduced the total melting time to 170 s—an 8.12-fold (or 87.68%) enhancement compared to the base case. These results highlight the critical role of fin placement in optimizing PCM melting, offering valuable insights for the design of more efficient thermal energy storage systems.