Topic: Freezing Dynamics and Morphology of Impacted and Deposited Droplets on a Cold Surface
Speaker: Professor Chun Yang, Nanyang Technological University (NTU), Singapore
Time: Monday, May 27, 2024, 10:00 a.m.
Venue: D407, Main Building, Shahe Campus
Abstract:
Icing of structures is a major hazard from aviation (e.g., aircrafts), to energy production (e.g., wind turbines), maritime (e.g., shipping, offshore oil rigs), and thermal systems (e.g., heat pumps, cold storage). Icing is usually resulted from a droplet impacting/depositing onto a cold surface and then freezing on the surface. In the past decades, the use of coatings of various materials for mitigating icing or de-icing, has been explored. Often wettability of coatings is used as a key indicator for its effectiveness in aiding with de-icing or mitigating the icing. This is due to the facts that wettability of a surface influences how a droplet will remain or can be removed from a surface and also surface wettability will determine the nucleation sites for ice or frost to form, which in turn will cause freezing of the water on the surface. Therefore, the phenomenon of droplet freezing on a substrate surface exhibits the strong coupling of multi-physics including droplet impact dynamics, surface wetting, and substrate cooling with phase change. This talk will discuss the freezing characteristics of impacting and deposited water droplets and nanofluids droplets under the effects of surface wettability, substrate temperature, and impact velocity. Both experimental and numerical simulation results will be reported.
About the Speaker:
Chun Yang is a Full Professor in School of Mechanical and Aerospace Engineering at Nanyang Technological University (NTU). He obtained his B.Sc. degree from the Department of Thermal Engineering at Tsinghua University, M.Eng degree in Engineering Thermophysics from University of Science and Technology of China, and Ph.D. degree in Mechanical Engineering from University of Alberta. Prior to joining NTU in 1999, he had been with Syncrude Canada Ltd. - Edmonton Research Centre under NSERC Chair Programme in Oil Sands for three years. His research lies in experimental, theoretical and numerical studies of electrokinetic transport and microfluidics, colloids and surface phenomena as well as fluid flow, heat and mass transfer at micro and nano-scales with emphasis on electrostatic surface charge and interfacial effects, exploring applications in water quality monitoring, thermal management, icing mitigation and de-icing, nanoenergy generation, etc. He has authored and co-authored one book, 24 book chapters and more than 260 refereed journal papers with Google Scholar citation counts of more than 17,000 and Hirsch-index over 60. He also has four US patents in his name. He had served as Editor for International Communications in Heat and Mass Transfer and Open Physics, and Associate Editor for Science Bulletin. Currently, he is Editor-in-Chief for Frontiers in Heat and Mass Transfer and also sits on the Editorial/Advisory Boards of several journals. He is a Fellow of American Society of Mechanical Engineers (ASME) and Asian Union of Thermal Science and Engineering (AUTSE).
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