University Events

Description: Mechanical Engineering (MNE) SEMINAR

DATE:
Friday, March 29, 2024

TIME:
2:00 p.m. - 3:00 p.m.

ZOOM:
https://umassd.zoom.us/j/91640406955?pwd=eklBZWVDOXVDa2VwUFMra1kwNWhjdz09
(Contact hling1@umassd.edu or scunha@umassd.edu for the Passcode)

SPEAKER:
Dr. Kianoosh Yousefi, Assistant Professor, Department of Mechanical Engineering, University of Texas at Dallas

TOPIC:
Turbulent Flow Structure Over Ocean Waves: From Experiments to Data-Driven Modeling

ABSTRACT:
About two-thirds of the surface of the Earth is covered by the ocean. The air-sea exchanges of mass, momentum, and energy that take place at the ocean surface over such a huge area play an integral role in determining the sea state, weather patterns, and climate and thus significantly impact many aspects of human life. In particular, surface waves, which most of us are familiar with from going to the beach, are crucial in connecting the atmosphere and ocean by generating turbulence, airflow separation, and breaking events. Although we know that surface waves are critically important, we do not yet fully understand the fundamental physics of ocean waves and their associated processes that couple the turbulent boundary layers above and below the ocean surface. This prevents us from making accurate model predictions of extreme wind events such as tropical storms and hurricanes. Over the last several years, we have investigated, in detail, the influence of surface waves on the structure of airside turbulence and flux transfers across the air-sea interface. In this presentation, I will outline the analysis of detailed laboratory measurements of airside velocity acquired above wind waves using a combination of particle image velocimetry (PIV) and laser-induced fluorescence (LIF) techniques. This data is further used to develop a supervised machine learning (ML) surrogate model for reconstructing the skin-friction drag over wind waves that can be used as a wall-layer model in large-eddy simulations.

BIO:
Dr. Kianoosh Yousefi is an Assistant Professor in the Department of Mechanical Engineering at the University of Texas at Dallas and the director of the Flow Dynamics and Turbulence (FDT) laboratory, an interdisciplinary research group dedicated to understanding the nature of turbulence in various environments. Dr. Yousefi received his Ph.D. in Mechanical Engineering from the University of Delaware in 2020. Prior to joining UT Dallas in 2023, he was an Associate Research Scientist in the Department of Civil Engineering and Engineering Mechanics at Columbia University and a Postdoctoral Researcher in the School of Marine Science and Policy at the University of Delaware. Dr. Yousefi’s expertise is in the experimental studies of turbulent air-sea interactions with a focus on applications in fluid mechanics, physical oceanography, and offshore renewable energy systems. His current research agenda is focused on understanding the physics of turbulent flows in atmospheric and oceanic boundary layers, surface waves, and the resulting generation of turbulence, airflow separation, breaking events, and spray/bubbles. Dr. Yousefi is the recipient of multiple awards, including several grants from the National Science Foundation (NSF OCE and CBET Divisions) and Department of Energy (DOE EERE Office), the Computing Innovation Fellowship from the Computing Research Association (CRA), and several early career scientist awards from the University of Delaware and Ocean Observatories Initiative. He is also a member of the American Physical Society (APS), the American Society of Mechanical Engineers (ASME), and the American Geophysical Union (AGU).

For more information, please contact Dr. Hangjian Ling, MNE Seminar Coordinator ( hling1@umassd.edu ).

All are welcome.

Students taking MNE-500 are REQUIRED to attend!

All other MNE BS and MS students are encouraged to attend. EAS students are also encouraged to attend.