Events Calendar

Aerospace & Mechanical Engineering Dept. Seminars

Speaker: Tonghun Lee , Associate Professor Department of Mechanical Engineering Michigan State University East Lansing, Michigan

Talk Title: Application of Laser and Optical Diagnostics for Study of Next Generation Propulsion Systems and Integration of Alternative Bio-derived Fuels

Abstract: Development of advanced propulsion systems of the future, such as hypersonic ramjets and pulsed detonation engines will require a deeper understanding of the reactive flow dynamics and chemistry in the relevant turbulent regime as well as development of new energetically enhanced combustion technologies. Additionally, these new engines will require seamless operation across a wide range of new and alternative bio-derived fuels as well as conventional hydrocarbon counterparts. This presentation will discuss recent progress in applying laser and optical diagnostics to study high Reynolds number reactive flows, plasma enhanced flames, as well as ignition and oxidation of alternative bio-derived jet fuels for potential integration in next generation propulsion systems. The following three topics will be discussed.

First is an effort to develop a continuous high-speed (>10 kHz) laser imaging system which integrates PLIF, PIV, and Rayleigh Scattering Thermometry (RST) for detection of temperature fields as well as velocity and chemical species. The proposed work will increased the number of detectable species in reactive flows by extending the wavelength range further into the UV with enhanced beam stability through non-linear optical engineering. Second is a novel concept of energetically enhancing the combustion by using a non-equilibrium plasma discharge. Highly efficient flame stabilization is achieved using a non-equilibrium plasma discharge by coupling the plasma energy directly into the reaction zone of the flame. The electrons and ions generated by the plasma introduce new chemical pathways which enhance and accelerate the combustion chemistry. The third topic of discussion is investigating the ignition and oxidation characteristics of bio-derived jet fuels. A rapid compression machine is modified for ignition testing of heavy fuel blends using a 'direct test chamber' fuel preparation method as well as optical access for laser and optical diagnostics.



Biography: Tonghun Lee is an associate professor in the Department of Mechanical Engineering at Michigan State University. Prior to working at Michigan State University, he was a graduate student at Stanford University where he obtained his M.S. (2002) and Ph.D. (2006) degrees in the 'High Temperature Gas Dynamics Laboratory.' His research is focused on utilizing laser and optical diagnostics to investigate new combustion concepts in advanced propulsion and energy conversion systems, with particular emphasis on supersonic air-breathing engines and high-pressure combustion research. He has been recognized with numerous awards including the AFOSR Young Investigator Award, the ONR Young Investigator Award, and the Presidential Early Career Award for Scientists and Engineers (PECASE).


Host: Professor Fokion Egolfopoulos

More Info: http://ae-www.usc.edu/seminars/9-12-12-lee.shtml

Location: Seaver Science Library (SSL) - Room 150

Audiences: Everyone Is Invited

Contact: April Mundy

Event Link: http://ae-www.usc.edu/seminars/9-12-12-lee.shtml