Unsteady flow oscillations, commonly known as combustion instabilities, were discovered in rocket and air-breathing engines in the late 1930s. Since then, combustion instabilities have plagued most, or practically all, engine development programs. Indeed, because of the high density of energy release in a volume having relatively low losses, conditions favor excitation and sustenance of flow oscillations in any combustion chamber intended for use in a propulsion system.
This seminar will provide an overview of combustion instabilities in four different types of propulsion systems (solid rocket, liquid rocket, gas turbine, and ramjet/scramjet engines). Emphasis will be placed on the present understanding of the processes involved, and contemporary research needs and challenges. Various research issues in acoustics, fluid mechanics, and chemistry related to oscillatory combustion in practical systems will be discussed. Both passive and active control techniques will be covered. Applications of contemporary numerical schemes, approximate analytical methods, and experimental diagnostic tools to combustion instability studies will be addressed.
Prof. Vigor Yang is presently Ralph N. Read Chair and Regents’ Professor at the Georgia Institute of Technology. He has published extensively in aerospace propulsion, combustion, and data science. Prof. Yang was the Recipient of the American Institute of Aeronautics and Astronautics (AIAA) Air-Breathing Propulsion Award (2005), the Pendray Aerospace Literature Award (2008), the Propellants and Combustion Award (2009), and the von Kármán Lectureship in Astronautics Award (2016). He was awarded the Worcester Reed Warner Medal (2014) by the American Society of Mechanical Engineers (ASME), and the Lifetime Achievement Award (2014) by the Joint U.S. Army, Navy, NASA, and Air Force (JANNAF) Interagency Propulsion Committee. He also received the Statistics in Physical Engineering Sciences Award (2019) from the American Statistical Association (JSA).
Besides, Prof. Yang is a member of the U.S. National Academy of Engineering, an Academician of Academia Sinica, and a foreign member of the Chinese Academy of Engineering. He is also a fellow of the AIAA, ASME, Royal Aeronautical Society, and Combustion Institute.