Melting Rate Analysis for Optimization of Fin Configuration in PCM Based Thermal Energy Storage System

Abstract

The increase in the energy demands and a higher peak hour electricity tariff makes thermal comfort management of buildings more expensive and critical. Thermal comfort at an optimum cost requires management of building heat load. This leads to the use of Phase Change Materials (PCM) for thermal energy storage system (TESS). The process varies with fin length, position and numbers. The process is complicated requiring either numerical or experimental modelling. Data analysis with statistical methods to understand the melting process under various fin configurations is presented here. Result from open literature has been extracted and equations for liquid fraction are generated using polynomial regression modelling. Melting rate is traced over time to account for the rate in change of the liquid fraction. Analysis showed that, during the initial phase until about 45% liquid melt; the time taken was independent of fin location but increased linearly with fin number. Surprisingly, during the melt process, the fin at top section has a higher melting rate in the initial phase but decreases rapidly. However, this decrease is stabilized and increased by the bottom fins in the later phase when the liquid fraction is in the range of 45% to 90% that simultaneously helps in decreasing the melt time. But this stabilization is affected if the number of fins at the top is more than bottom.