Thermosiphon Optimization Phase Change-Study on Heat Transfer Performance of Thermoelectric Systems

Applying heat storage technology based on phase change materials (PCM) to thermoelectric conversion (TEG) systems can significantly extend the heating and power generation time, but there is still an urgent need to strengthen PCM heat transfer in order to expand its application scope. Thermosiphon (TS) is a high-efficiency heat transfer element that utilizes the phase change of its internal heat transfer medium to achieve thermal conductivity far exceeding that of metal. Introducing TS into PCM-TEG is expected to further improve thermal energy utilization, but to achieve optimal utilization efficiency, the three components need to be adapted to each other. This work studies the influence of different fin structure heat storage tanks and TEG cooling conditions on the power generation performance of the PCM-TS-TEG coupling system. The results show that under the condition of stacked fin heat storage tank and natural cooling, the TEG hot end temperature can obtain higher heat of 146.47°C. Compared with the non-finned heat storage tank, the temperature of the TEG hot end is increased by 10.95°C, which makes the PCM-TS-TEG coupling system increase the output power by 39.29% during the PCM phase change condensation process; based on the stacked fin heat storage tank, the water cooling condition is a flow rate of 26 rpm, the electrical energy obtained by the system reaches up to 898.75 J, which is 7.46 times higher than that of natural cooling.