Generation, Manipulation, and Applications of Monodisperse Droplets

Speaker :
Prof. Weiwei DENG
Professor of Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology
Date : 25 Oct 2019 (Fri)
Time : 3:30 pm
Venue : LT-L, Cheng Yu Tung Building, HKUST


Droplets of liquid solutions and suspensions are building blocks for additive manufacturing such as printing and spray deposition. Superior product quality depends on both the droplet generation process and the final stage of interaction with the substrate. In this talk I will first discuss our precision atomization technology portfolio that generates monodisperse droplets in a wide size range. We achieved unprecedented controllability and precision through breakup of liquid jets with deliberately triggered instabilities. I will show the fascinating outcomes of the breakup of electrified jets that undergo two different instabilities (varicose and whipping). Then I will show report an elegant phenomena that naturally and beautifully links optical radiation pressure, total internal reflection, capillary wave, and Rayleigh-Plateau instability together. I will also share our recent discovery on droplet impact on solid substrates that involves gas entrapment phenomena, which often lead to defect formation during 2D functional and 3D structural printing. I will conclude with a few applications such as printing perovskite solar cells.


Dr. Weiwei Deng is a Professor in the Department of Mechanics and Aerospace Engineering at the Southern University of Science and Technology (SUSTech). Prior to joining SUSTech, he was a tenured associate professor at Virginia Tech (2015-2017) and an assistant professor at the University of Central Florida (2010-2015). He is the recipient of National Science Foundation CAREER Award in the United States. He obtained his Ph.D. in Mechanical Engineering from Yale University and B.S. from Tsinghua University in China. Dr. Deng’s general research interest is the experimental fluid dynamics of low-dimensional liquid subjects (droplets, jets, and films) and their applications in additive manufacturing. His group’s work has been featured as the cover articles of Soft Matter and Physical Review Letters.