Research on Variable Structure Performance of Active Electrocaloric Refrigeration Devices

The optimization of regenerator geometries to enhance the performance of active electrocaloric regenerators (AERs) has attracted significant attention. In this study, corrugated and tapered structures were applied to a parallel-plate AER, and the effects of electrical field parameters on device performance were compared. The results indicated that the tapered structure better balanced the flow resistance and heat transfer efficiency, thus achieving the best refrigeration performance under the same operating conditions, followed by the corrugated AER structure. Short or long device cycle periods resulted in poor refrigeration performance. The electrical field should be switched when the transferred heat reaches 63%-66% of its maximum value. For the same cycle period, each device exhibited an optimal polarization duration (0.2 s), during which the refrigeration capacities of the parallel-plate, corrugated, and tapered AERs were 4.16 W, 4.35 W, and 4.71 W, respectively, with corresponding coefficients of performance of 1.76, 2.04, and 3.17. As the electrical field intensity increases, the refrigeration capacity of the device increases exponentially. The greater the field intensity, the greater the improvement in the refrigeration capacity of the gradually shrinking AER. When the field intensity increased from 50 MV/m to 225 MV/m, the refrigeration capacity of the tapered AER increased from 0.68 W to 10.06 W, an improvement of approximately 13.79 times.