Li, Miljkovic research published in Science Advances

Science Advances has published recent work from MechSE postdoc Jiaqi Li and Associate Professor Nenad Miljkovic.

Their research article is titled, “Liquid film-induced critical heat flux enhancement on structured surfaces.”

“I think this work has important implications for the study of bubble hydrodynamics, such those observed in pool and flow boiling heat transfer, aeration and cavitation, microfluidics systems, and electrochemical catalysis,” said Li, the first author on the paper. “We first visualized the thin liquid film underneath the bubble on structured surfaces using a method we developed called in-liquid endoscopic visualization. We used this method to characterize the liquid film evolution during bubble growth. We clarified the significance of the micro/nanostructures on bubble behavior.”

Read the full article in Science Advances.

Abstract

Enhancing critical heat flux (CHF) during boiling with structured surfaces has received much attention because of its important implications for two-phase flow. The role of surface structures on bubble evolution and CHF enhancement remains unclear because of the lack of direct visualization of the liquid- and solid-vapor interfaces. Here, we use high-magnification in-liquid endoscopy to directly probe bubble behavior during boiling. We report the previously unidentified coexistence of two distinct three-phase contact lines underneath growing bubbles on structured surfaces, resulting in retention of a thin liquid film within the structures between the two contact lines due to their disparate advancing velocities. This finding sheds light on a previously unidentified mechanism governing bubble evolution on structured surfaces, which has significant implications for a variety of real systems using bubble formation, such as thermal management, microfluidics, and electrochemical reactors.