Elucidating phase-change heat transfer mechanisms and their role in developing next generation energy systems

Abstract:
Liquid–vapor phase change is one of the most effective ways to absorb and reject thermal energy, yet many of the mechanisms governing phase-change heat transfer remain poorly understood. In this talk, I will discuss our recent advances in optical diagnostics that have enabled us to directly probe the physics of boiling heat transfer. We find that bubbles substantially enhance single-phase liquid heat transfer by increasing turbulence within the liquid, enabling a simple model that predicts the boiling curve from optical measurements alone – without machine learning. I will also discuss our measurements of microlayer evaporation, where a new spatial-temporal analysis technique enables accurate determination of microlayer thickness and accommodation coefficient, and motivates a boundary-layer-based scaling law for the initial microlayer thickness. Together, these studies demonstrate how advanced optical measurements can reveal previously inaccessible heat-transfer mechanisms and translate them into predictive models that provide a foundation for designing next generation thermal energy systems.

Biography:
Matt Hughes is an Assistant Professor in the Department of Mechanical Engineering at University of Michigan and currently an editor of the journals Applied Thermal Engineering and AI Thermal Fluids. He was previously a Research Scientist in the Department of Nuclear Science and Engineering at Massachusetts Institute of Technology.  His research focuses on the fundamentals of multi-phase flow and heat transfer, autonomous operation of thermal hydraulic systems and experiments, and advanced thermal system design.