Thermal management of power modules based on the hybrid cooling system: Phase change material with coolant fluid

Abstract Keeping the operating temperature in the allowable range of the power module, under a very high heat flux, is of particular importance in the performance of the systems and their reliability. In this investigation, a new hybrid thermal heat sink consisting of phase change material with different arrangements and mass flow rates has been used for cooling an Insulated‐gate bipolar transistor. As an innovation, to reduce the operating temperature of the power module at a heat flux of 100 W/cm 2 , paraffin and metal‐based PCM have been applied in the water cooling chamber and simulated simultaneously. The finite volume method and piezo algorithm were used to solve the governing equations. The melting process of the PCM was simulated by the enthalpy‐porosity method in a three‐dimensional domain. The comparison of local temperature distribution among four models (A–D) shows that Case D reduced the operating temperature by about 15% versus other arrangements, and at flow rates of 0.0025–0.005 kg/s achieved up to 3°C lower than pure fluid. For paraffin ( k = 0.12 W/m·K, L = 255,000 J/kg), Fo·Ste. at 3600 s is 0.0904, while for the metal alloy ( k = 33.2 W/m·K, L = 202,000 J/kg) it is 6.5052, indicating much faster melting. The metal‐based PCM, with higher conductivity and lower latent heat, enhances heat transfer and rapid cooling, whereas paraffin, with slower melting, suits long‐term energy storage.