Abstract
The need for anti-frosting surfaces is continued and ever-present. Whereas de-icing surfaces aim to reduce the adhesion of frost for easy removal, anti-frosting surfaces aim to intrinsically resist frost formation. Long-term frost resistance is incredibly valuable for regions that regularly experience freezing conditions, especially for above-ground power/telecommunications cables, aircraft airfoils, and satellite dishes, among numerous other applications. Here, we introduce new guidelines for multi-scale surface designs that passively promote increased frost-free regions over long periods of time. By combining geometries and material properties over multiple length scales, we can effectively manipulate the diffusion flux field of incoming water vapor to create two distinct regions: (1) a small, sacrificial region with the majority of frost growth and (2) a large non-frosted region that resists frost growth over time. While millimeter-sized features alone can partially have this effect (i.e. frost-free areal portion = ~38%), it can be enhanced to a frost-free areal portion of nearly 95% by the addition of Graphene Oxide (GO) dough. Utilizing the properties of GO doughs, namely permeability and anisotropic heat transfer, in conjunction with anisotropic mass transfer on macrotexture, we can successfully control the size of the frost-free region for longer than several days, thereby mitigating frost-related material/performance degradation.
About the Speaker
Dr. K.-C. Kenneth Park joined the Department of Mechanical Engineering as an Assistant Professor in 2017. He received his BS in mechanical and aerospace engineering from Seoul National University in South Korea in 2008 and his MS and PhD in mechanical engineering from the Massachusetts Institute of Technology in 2013 supported with the Xerox-MIT Fellowship and Samsung Scholarship. He then worked as a postdoctoral fellow in the John A. Paulson School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering at Harvard University in 2013-2016. During his PhD and postdoctoral research, he received four awards including the MIT Wunsch Foundation Silent Hoist and Crane Award for Outstanding Graduate Research and Harvard Postdoctoral Award for Professional Development. He was selected as a recipient of the Hanwha Non-Tenured Faculty Award in 2021. His research group works on bio-inspired surface engineering problems and interfacial transport phenomena.
Host: Professor Randy Ewoldt
