Influence of Partitions and Eccentricity on the Phase Change Material Melting in Double‐Tube and Triple‐Tube Latent Heat Storage Systems

ABSTRACT It is evident that the future world fundamentally requires developed energy storage systems to balance energy production and demand, thereby preventing energy waste. One innovative and appealing approach in this field is the utilization of phase change materials (PCMs). Heat exchangers are among the most widely employed PCM‐based energy storage systems utilized in several applications. The current study aims to improve the energy storage performance of two configurations of double‐tube and triple‐tube heat exchangers. In this context, the impact of rigid separators on the melting process is examined for both configurations. Additionally, the interplay between the partitioning effect and the relocation of inner heat transfer fluid (HTF) in both concentric and eccentric configurations is investigated. The simulation is carried out using the enthalpy–porosity approach, implemented through the FVM. Accuracy of the numerical method is assessed by a comprehensive validation study. Results indicate that, in the concentric and eccentric configurations of the double‐tube design, the optimal cases are those with four and eight partitions, which demonstrate a decrease in melting duration by 8.95% and 39.02%, respectively. For the concentric configuration of the triple‐tube design, the most effective case is the twelve partitions, resulting in a 30.99% decrease in melting time. Conversely, in the eccentric design, the application of partitioning causes an increase in melting time.