Study on the melting characteristics of composite phase change materials and the power generation performance of coupled thermoelectric systems under supergravity conditions

Miniaturization and integration of electronic equipment in aircraft have resulted in a substantial increase in thermal load. However, aircraft often experience acceleration maneuvering flights in supergravity environments, which makes comprehensive research on thermal management under supergravity conditions necessary. The influence of gravity on the thermal storage properties of composite phase change materials doped with graphene nanoparticles (GNP-PCM) was investigated in this study by simulation. Under 2g, 4g, 6g, 8g, and 10g gravity conditions, the melting time is reduced by 14.86%, 27.05%, 33.31%, 37.00%, and 39.79%, respectively, compared with normal gravity conditions. Moreover, the integration of the PCM with a thermoelectric power system facilitated waste heat utilization. Incorporating GNPs markedly enhances power generation efficiency under 10g supergravity conditions. With an open-circuit voltage of 0.8 V and a maximum output power of 0.11 W, the power generation reached 81.62 J, which is 53.91% higher than that of pure PCM. This enhancement can be attributed to the improved natural convection and accelerated melting rate facilitated by the GNPs. This study elucidates the underlying physical mechanisms affecting the melting rate of PCM under increased gravity conditions. Furthermore, coupling PCM with a thermal power generation system provides a rational approach for the reuse of waste heat.