Experimental Investigation of a Finned Pentaerythritol-based Heat Storage Unit for Solar Cooking at 150-200 ̊C

An experimental study on the charging and discharging performance of a finned thermal energy storage unit (TESu) that utilizes pentaerythritol (PE) as phase change material (PCM) was conducted. It is known that fins enhance the heat transfer within TESu, however, the optimum PCM to fin volume ratio for a particular application is usually unknown. Therefore, this work compares the charging and discharging performances of three rectangular TESu prototypes with 6, 12, and 21 PE to fin volume ratio (P/F) per prototype. The performance comparison was in terms of (1) charging rapidity, (2) heat retention effectiveness, (3) temperature distribution, and (4) the cooking power. It is found that for 6 ≤ P/F ≤21, charging rapidity decreases with PE/fins ratio. On the other hand, the PE/fin volume ratio of higher than P/F > 12 has great influence on heat retention effectiveness, temperature distribution in the TESu, and cooking power. Therefore, 6 < P/F <12 strikes a balance between charging rapidity and discharging performance (heat retention time, improved temperature field as well cooking power). However, generalization to TESu for cooking application pends extension of this work to other PCM operated TESu.