Enhancing Phase Change Material (PCM) efficiency through timely melting-solidification cycle interruption

We present a multifaceted study on heat transfer in phase-change materials (PCMs), focusing on both melting and solidification phases, different temperature scenarios, an assessment of practical implementation aspects, and Marangoni convection. This research on n-eicosane complements our previous work [1], which focused on gallium. For both PCMs, the most effective scenario involves switching temperatures between cold and hot walls at a certain moment, which occurs earlier than the full melting time or reaching steady state. This specific moment corresponds to the beginning of a decrease in heat extraction efficiency. The success of this scenario relies on the symmetric thermal boundary conditions and multi-cyclic temperature inversion. We suggest that the implementation of this scenario is similar to rotating the PCM body within its package while maintaining the temperature of the external walls constant. This study also highlights the importance of Marangoni convection in heat transfer mechanisms.