The Laminar Flame to Turbulent Flame to Detonation Transition: Studies of Non-Kolmogorov Turbulence

Elaine S. Oran Senior Research Scientist
Naval Research Laboratory Lecture Abstract "The transition from a propagating subsonic Laminar flame to a high-speed Turbulent flame and then to supersonic Detonation wave (the LTD transition) involves a series of often dramatic events involving changes in the nature of the reaction wave. Some of the events develop continuously whereas others appear suddenly and with little apparent warning. The LTD transition occurs in highly exothermic energetic materials, for example in hydrogen-air mixtures resulting from gas leaks at hydrogen production and storage facilities as well as in carbon-oxygen mixtures in white-dwarf stars which, after ignition, become thermonuclear supernovae. This presentation describes the properties of the LTD transition using videos made from numerical solutions of the multidimensional, unsteady, chemically reacting, Navier-Stokes equations. The discussion focuses on selected features of the flow, including: formation of a turbulent flame and the nature of the turbulence, creation of hot spots as the origins of detonations, effects of stochastic processes on our ability to make predictions, and comparisons between simulations and experimental data." Professor Oran, Gas Dynamics Laboratories, designs numerical methods for simulating complex fluid dynamic processes, and then uses these methods to solve complex fluid dynamic processes and a wide variety of other scientific and engineering problems. Her recent research interests include combustion and propulsion, rarefied gases and microfluidics, fluid turbulance, materials engineering, high-proformance computing and parallel architectures, computational science and numerical analysis, biophysical fluid dynamics, wave equations, and astrophysical phenomena such as supernova explosions and jets. Oran has authored over 200 refereed journal articles as well as many conference papers and presentatoins. She is also the co-author of the book Numerical Simulation of Reactive Flow (2nd edition, Cambridge Press, 2001).

Location: Davidson Conference Center -Club Room 2nd Floor

Audiences: Everyone Is Invited

Contact: April Mundy