Selamet, Ahmet

Biography

Ahmet Selamet received his Ph.D. in Mechanical Engineering (ME) from University of Michigan in 1989. He joined the ME Department of The Ohio State University (OSU) in 1996, where he holds the rank of Professor since 2001. From July of 2012 to June of 2016, he served as the elected Chair of the Department of Mechanical and Aerospace Engineering at OSU. His research centers around the breathing system of internal combustion engines, nonlinear wave dynamics, combustion, fluid mechanics, and heat transfer. He has published more than 250 articles in journals/proceedings and co-authored a book on Heat Transfer. His recognitions include Harrison, Lumley, Innovators, and MacQuigg Awards from OSU; and Teetor Educational Award and Hillquist Lifetime Achievement Award from Society of Automotive Engineers (SAE). He is a Fellow of the Acoustical Society of America (since 2001) and SAE (since 2003).

Expertise

Prof. Selamet’s research focuses on internal combustion engines, fundamentals of linear/nonlinear wave dynamics, noise and pollutant emission control, internal fluid flows, combustion, fluid mechanics, and heat transfer. For more than three decades, he has performed extensive analytical, computational, and experimental work to understand the unsteady flow and wave dynamics in engine breathing systems (induction/combustion chamber/exhaust.) Throughout this time, his efforts have primarily concentrated on developing and validating models for the breathing system physics to improve the performance and acoustics predictions in engine simulation codes. Prof. Selamet has excelled in combining the analytical and computational approaches in engine modeling with the experiments in the state-of-the-art facilities (Flow, Engine, Acoustics, and Turbocharger Research Laboratories) he has built at the Center for Automotive Research.

Research also explores innovative concepts to simultaneously (a) improve the engine performance, including fuel efficiency, (b) suppress the flow-generated and/or airborne noise, and (c) minimize the pollutant emissions. 

While the primary emphasis of studies has been the development of fundamental understanding and validation of the resulting models, the in-depth knowledge gained in the process is also used to produce design guidelines and novel bench techniques. 

The rise of turbochargers as implemented recently in downsized and boosted spark ignition engines to improve fuel efficiency and reduce emissions has led, for example, to meticulous efforts during the last decade through a unique bench-top turbocharger research laboratory supported by a Particle Image Velocimetry system in addition to the other advanced time-resolved measurement capabilities and nonlinear flow simulations. Key objectives of these critical turbocharger inquiries have been to:

· Characterize the performance of both the compressor and turbine of turbochargers, capable of extending beyond the conventional knowledge, including reverse flow; 

· Capture the unsteady pressure and velocity fields resulting from flow instabilities (due to surge) in centrifugal compressors at low flow rates both experimentally and computationally; 

· Examine the broadband noise associated with flow separation within compressors and discrete tones due to surge and/or blade passing;

·  Understand the inherent steady and unsteady physics better, particularly within the compression system, leading to the development of improved predictive tools, including for surge;

·  Incorporate design changes to attenuate or delay surge.

The impact of contemporary research in his laboratories has been extraordinary throughout the decades particularly in the following areas: (a) developing reliable models for engine simulations as validated by experiments; (b) identifying and isolating pertinent physics from engines and duplicating these scientific puzzles on a bench-top environment for a more in-depth examination, leading to original knowledge creation and dissemination; (c) promoting a learning environment that always couples laboratory measurements and computational predictions, while striving to shrink the gap between the two approaches, thereby making the predictions  ultimately powerful design tools; (d) building an exemplary collaborative relationship with the automotive industry; and finally, yet perhaps most importantly, (e) successfully educating the young minds to contribute to the future of the mobility and the society.