Configuration design, heat transfer analysis and performance evaluation of a novel asynchronous stacked electrocaloric refrigeration device

Abstract

Electrocaloric refrigeration, as a sustainable refrigeration technology, remaining numerous challenges in the refrigeration efficiency and/or capacity of the existing reported electrocaloric refrigeration devices. In this study, a novel asynchronous stacked electrocaloric refrigeration device (ASERD) model is firstly proposed. The ASERD model enables simultaneous heat absorption and release within a single refrigeration cycle, thereby maintaining a significant vertical thermal gradient between the upper and lower electrocaloric sliding layers. This creates a “thermal wall” effect that impedes horizontal thermal reflux from the heat dissipation side to the microchip side, reducing the temperature at the microchip side by approximately 5 K compared to synchronous design. Secondly, six typical microchip local dynamic hotspots are designed to verify the ASERD model’s anti-interference ability to heat load fluctuations. During regulation process, the “thermal wall” effect continuously strengthens, resulting in increasing refrigeration performance. The maximum temperature rise is reduced by 9.87 K, 8 K, 9.51 K, 8.92 K, 6.85 K, and 6.98 K, respectively. Thirdly, two main regulation strategies for refrigeration performance enhancement are studied for ASERD model with higher degree of freedom: field intensity and motion frequency. In these two regulation strategies, two overregulated phenomena caused by heat conduction overshoot: temperature feedback and refrigeration reversal phenomenon are discussed in field intensity regulation. Based on above analysis, a hierarchical regulation strategy for refrigeration performance enhancement combining field intensity and motion frequency is proposed, further reducing maximum temperature rise by 10.65 K and 6.96 K compared to optimal single regulation. In summary, the feasibility of ASERD model is verified in principle, which achieves better refrigeration capability compared to conventional synchronous design. Besides, flexible regulation strategy for ASERD model is discussed to further improve the refrigeration performance. Therefore, the novel ASERD model demonstrates better potential application prospects.