Thermodynamic model for self-actuated electrocaloric cooling thermal management

Self-actuated electrocaloric cooling offers a promising solution for microelectronic thermal management, but its development is hindered by the lack of thermodynamic models capturing heat transfer behavior by electrostrictive deformation. To address these challenges, a thermodynamic model is proposed, which accounts for the dynamic thermal resistance in heat transfer with electrostrictive deformation and coupled “electrical - mechanical - thermal” multiphysics processes. First, the electrostrictive deformation of the electrocaloric polymer film is modeled as a symmetric deformation problem under a uniform central load on a circular film. Next, the dynamic thermal resistance at the film's interfaces, as quantified by the deformation model, is incorporated into a “heat source - film - heat sink” thermal conduction equation to predict the temperature evolution and coefficient of performance (COP) in thermodynamics analysis. Furthermore, experimental validation confirms the accuracy of both the electrostrictive deformation model and the thermodynamic cycle temperature predictions. The average RMSE for the predicted temperature changes at the center, edge, and for the average over the active zone is 0.130 K, 0.114 K, and 0.128 K, respectively. Finally, numerical analysis reveal that greater deformation and lower contact thermal resistance (RI) improves both the COP and the temperature difference of the heat source (ΔTh), while the non-contact thermal resistance (RO) exhibits a non-monotonic effect on COP but a monotonically positive effect on ΔTh. This work establishes a thermodynamic foundation for developing high-performance, low-power electrocaloric cooling systems toward sustainable thermal management in electronics.