Visitor Seminar: “Phase Change Heat Transfer for Water and Energy Sustainability”

Abstract:

Imagine that one day you can drink water wherever air is available, you can grow plants on Mars, you can drive flying cars, and your smartphone never gets hot. Phase change heat transfer will be an essential process in these systems and devices. Condensation and evaporation are two of the most important phase change processes as they have high heat transfer rates. In condensation, the condensate must be rapidly removed to reduce the thermal resistance. In evaporation, the liquid must be rapidly supplied to promote thin film evaporation. This presentation will cover both fundamental studies and prototype development by showing new understandings and practical applications. We will first develop a new theoretical model for dropwise condensation, and then use the new model to guide the innovative design of a vapor-liquid separation process that provides exceptional performances in phase change heat transfer. Unlike the current technologies that show reduced heat transfer coefficients at increased heat fluxes, the vapor-liquid separation condensation mode can maintain the exceptional heat transfer coefficient at elevated heat fluxes. We will also show our work on transpiration-inspired capillary evaporation in porous structures. Finally, the condensation and evaporation research outcomes will be integrated into a vapor chamber prototype for the thermal management of electronics. We envision that our fundamental studies will lead to broad impacts on water and energy sustainability.

Bio:

Dr. Xianming (Simon) Dai is an assistant professor of Mechanical Engineering at The University of Texas at Dallas. He is a recipient of the National Science Foundation CAREER Award in 2021 and the Army Research Office Young Investigator Award in 2019. He received the Outstanding Early Career Award at the 2021 micro Flow and Interfacial Phenomena Conference for outstanding and significant contributions to the fields of surface wettability, phase-change heat transfer, and water harvesting. His students won the ASME Best Poster Award in Micro and Nano Technology, and the 1st place prize in the STEM Bridge Summer Program. Dr. Dai earned his Ph.D. degree at the University of South Carolina, and his M.S. and B.S. degrees at Huazhong University of Science and Technology and Chongqing University. His research interest includes bioinspired thermal fluids with broad impacts on water and energy sustainability.