Integration of thermal insulation and thermoelectric conversion embedded with phase change materials

The thermoelectric effect can convert waste heat into electricity. The present work presents an integrated system of Thermoelectric Generators (TEG) and Phase Change Materials (PCMs) for thermal insulation of high-speed vehicles, where high heat fluxes of large fluctuations make thermal protection and energy harvest challenging. A single-stage thermoelectric generator is prepared with phase-change materials embedded to absorb and convert excessive heat. The performance is evaluated experimentally and numerically, between which a reasonable agreement is observed. The maximum temperature at the outside surface is reduced by 200 K, and the temperature curves are flattered. Furthermore, two-stage and two-segment integrated systems are numerically evaluated, generating a data set of thermoelectric performance. An artificial neural network is developed for prediction and a genetic algorithm is employed for optimization. The maximum specific power can be improved to 570 W/m2 in the two-segment system, while the temperature variation at the hot side of TEG in the two-stage system can be reduced to 230 K. Finally, a discussion on the effects of PCMs parameters is performed. Overall, the present work not only demonstrates the feasibility of such an integrated system but also illustrates the whole procedure of the predictions and optimizations. This could inspire more development for advanced integrated systems for thermal management.