An Ultrasonic-assisted Nanofluid Direct Contact Liquid-based Battery Thermal Management System

A novel battery thermal management system (BTMS) is proposed in this work by incorporating hybrid heat transfer enhancement mechanisms, where the ultrasonic-assisted nanofluid immersion cooling metho is employed. A large number of diamond nanoparticles are suspended in the base fluid, exhibiting insulating characteristics, engages in immersion liquid cooling system with a mini-channel structure. Additionally, the application of ultrasound further intensifies the heat transfer effect. An experimental study is conducted to analyze the individual impact of various variables on temperature characteristics through the single factor analysis, including the volume flow rate, nanoparticle concentration, ultrasonic frequency and power. On this basis, the proposed system is optimized by considering multiple factors. The experimental results demonstrate that the optimized BTMS exhibits superior performance in both heat transfer efficiency and system temperature uniformity, with the maximum temperature being less than 35.2 °C, and the maximum temperature difference can be controlled within 1.6 °C.