Professor NaguibDr. Ahmed Naguib Professor of Mechanical Engineering
Michigan State University
Unsteady Wall Pressure and Heat Transfer Associated with Near-Wall Vortex Pairing
Location: ARC 100
Ahmed Naguib
Naguib is currently a Professor of Mechanical Engineering at Michigan State University. He served as the Associate Chair for the Graduate Program from 2012 to 2014. His B.S. degree is from Ain Shams University, Cairo, Egypt, and Master's and Ph.D. degrees are from Illinois Institute of Technology, Chicago, USA. His research interests are in experimental fluid dynamics and associated applications, particularly in the field of turbulence and flow instability physics and control, unsteady aerodynamics as well as development of measurement techniques. Prof. Naguib’s work has resulted in more than eighty conference and journal publications, two book chapters, and three patents. He also served as Associate Editor of the American Institute of Aeronautics and Astronautics (AIAA) Journal for nine years, and is an Associate Fellow of AIAA.
Abstract
This study is motivated by understanding the fundamental phenomena arising from vortex-wall interaction in impinging jets. The particular focus is on the unsteady wall pressure and the thermal transport resulting from such interactions. The former is significant to engineering problems involving flow-induced noise and vibration, while the latter is relevant to the use of impinging jets in cooling/heating applications. Our recent experimental work shows that particularly strong interactions occur when the jet-to-impingement-wall spacing is such that pairing of the jet vortices takes place while the vortices advect parallel to the plate. To gain insight into the interaction physics affecting the unsteady wall pressure and heat transfer during near-wall vortex pairing, simple model problems involving the interaction of a pair of axisymmetric vortex rings with a flat wall are examined computationally. The resulting spatiotemporally resolved velocity, pressure and temperature fields are employed to establish connections between the surface effects and the flow features. The outcome is benchmarked against its counterpart for a single vortex ring interacting with the wall.
