Two-Phase Immersion Cooling for Short-Duration High-Power Electric Motors

In response to the extreme heat dissipation challenges faced by short-term high-power motors, this paper proposes a solution based on two-phase immersion cooling. Unlike traditional cooling methods, this study analyzes motors subjected to high current density over a short period, utilizing the latent heat in the phase change process of the coolant to achieve efficient heat dissipation. During the experiment, the stator assembly was immersed in a dielectric liquid, and the short-term high-power operating conditions were simulated by controlled power input. The study focused on analyzing the relationship between superheat and heat flux and convective heat transfer coefficient (CHTC), and a boiling start time and power prediction model was established. Experimental results show that under short-term high-power conditions, this cooling method can achieve significantly higher heat transfer efficiency than traditional technologies, and the convective heat transfer coefficient can reach up to 2740 W/(m²·K). This study provides a new thermal management solution for short-duration high-power motor applications in aviation and other fields, and passive and efficient cooling can be achieved without an external pump system.