Seminar: Boundary Layer Flashback in a Swirl Combustor

Abstract

To reduce greenhouse gas emissions, hydrogen-enriched natural gas is being considered for use in stationary gas-turbine power generation systems. However, combustors are typically designed to operate with natural gas and so they are susceptible to flashback owing to the faster kinetics of the hydrogen-enriched fuels. Flashback occurs when the flame propagates upstream into the mixing tube and can lead to catastrophic failure of the combustor. To improve our understanding of flashback, we are conducting an experimental study of boundary layer flashback of lean-premixed, confined swirling flames. High-speed chemi-luminescence imaging, three-component time-resolved particle image velocimetry (PIV), and time-resolved tomographic PIV are being applied to study the flame-flow interaction inside the mixing tube during flashback. The seminar will focus on a discussion of the physics of boundary layer flashback in a swirling flow, including how it differs from flashback in 2D channels. Furthermore, differences in flame propagation behavior with varying hydrogen-content fuels will be addressed.

About the Speaker

Dr. Noel Clemens holds the Bob R. Dorsey Professorship in the Department of Aerospace Engineering and Engineering Mechanics at The University of Texas at Austin and serves as department chair. He received a B.S. in Mechanical Engineering from the University of Massachusetts/Amherst in 1985, and M.S. and Ph.D. degrees in Mechanical Engineering from Stanford University in 1986 and 1991, respectively. From 1991 to 1993 he was a post-doctoral fellow at the Combustion Research Facility at Sandia National Laboratories in Livermore, CA. Dr. Clemens began as an Assistant Professor at UT in 1993 and was promoted to full professor in 2005. His areas of research include turbulent mixing, combustion, laser diagnostics, shock wave/boundary layer interactions, inlet unstart and high-speed flow control. He received the Presidential Faculty Fellow Award in 1995, the College’s Faculty Excellence Award in 1997, the award for “Outstanding Teaching by an Assistant Professor” in 1998, the ASE/EM Department Teaching Award in 2000, and the Lockheed Martin Award for Excellence in Engineering Teaching in 2011. He is a Fellow of the American Physical Society and he served as Editor-in-Chief of Experiments in Fluids from 2009 to 2012.

Hosted by Professor Datta Gaitonde