Structural optimization of melting process of a latent heat energy storage unit and application of flip mechanism

Thermal energy storage technology is of great significance for the efficient utilization of solar energy. In this paper, the melting process of a horizontal latent heat energy storage unit is studied by numerical method. Taguchi design method and response surface method are exploited to optimize its melting performance. The effects of inner tube eccentricity, fin deflection angle, and fin width upon the melting performance are investigated. The contribution of each parameter to the melting performance is processed by Taguchi method, and the interactions of each parameter are obtained by response surface method. The fluid-structure coupling equation of target response is fitted to obtain the optimal structure, and the influence of different structural parameters on the melting performance is discussed. The results reveal that compared with the initial structure, the melting time of the optimal structure is reduced by 64.16% and the average heat absorption rate is increased by 168.38%, respectively. It is evaluated that the structure optimization greatly increases the heat absorption rate and reduces the melting time, but it has a negative effect on the heat absorption in one melting cycle. Finally, the single flip mechanism is introduced innovatively, and the influence of flip time on the related melting properties is discussed. The single flip is the best to increase the average thermal energy absorption rate by 6.30% and reduce the melting time of the unit by 10.57%.