Feasibility study of two-phase immersion cooling in closed electronic device

摘要

Feasibility of two-phase immersion cooling in a closed electronic device such as a microwave transmitter is experimentally investigated. Two-phase immersion cooling directly cools multiple heat sources with various shapes which enables simple and flexible thermal design by fulfilling the existing electronic device with a coolant. The challenge is to reduce internal thermal resistance from heat sources to the chassis surface by effective thermal diffusion induced by two-phase immersion. The study covers selection of coolant and effect of coolant filling ratio. Then heat dissipation performance by single and multiple heat sources as well as enhancement by two-phase immersion with conduction materials are experimentally tested. Leaf spring and coil spring, both made of phosphor bronze, are used as the conduction materials and compared with rigid copper block in two-phase immersion. Experiment setup contains a vertical heating plate and an outer wall with heatsink separated by a gap space. Thermal resistance of basic two-phase immersion and enhancement by conduction materials are compared to provide design guideline for two-phase immersion application in a closed device.