Uncovering the secrets of the liquid microlayer: towards next-generation thermal management of extreme power electronics

Two-phase immersion cooling is an emerging technology to deal with ever-increasing heat load of electronics clusters, in which heat is dissipated through boiling on hot surfaces. Due to highly-dense layout of the electronics, scenarios of confined space and vertical surfaces are commonly encountered in the two-phase immersion cooling. A key physical process related to boiling is near-wall liquid microlayer dynamics, serving as a major heat transfer mechanism to bubble growth, which needs explored. This project will develop advanced optical diagnostics to achieve high-resolution measurement of liquid microlayer in confined boiling. Through the present project, it is expected to extend the liquid microlayer insights from pool boiling to confined boiling, and comprehensively understand the dependence of the microlayer on the confined space, surface orientation and surface wettability, filling the research gap of lacking insights into the liquid microlayer in confined conditions. and enriching relevant theory to develop two-phase cooling technologies. Such better understanding of the microlayer could show a direction to enhance bubble growth and consequently boiling performance by altering boiling surfaces to trigger early microlayer evaporation and augmentation.