Melting regime maps to characterize heat transfer during solid-liquid phase change

Latent thermal energy storage (LTES) systems with phase change materials (PCMs) are a promising technology to store intermittent, renewable energy. However, the development of accurate and efficient design methods still remains a challenge, due to the transient behavior of these systems. This study investigates the melting process in rectangular enclosures heated from one side wall at constant temperature. To study the melting behavior, the melting regime theory of Jany and Bejan (1988) is applied, which states that the melting process can be divided into distinct melting regimes, each with their own characteristic heat transfer behavior. First, heat transfer occurs mainly through conduction. Once enough liquid PCM is formed, natural convection will come into play and become the dominant mode of heat transfer. Previous studies often overlook the distinction between the different regimes, potentially compromising the accuracy of their results. This project aims to address this limitation by separately characterizing the heat transfer in each melting regime and identifying the conditions under which the transitions occur. The combination of the correlations for heat transfer and the transitions is referred to as 'melting regime map'. The poster presents an overview of our current findings based on literature data, and the remaining research gaps.