Fri, Apr 05, 2019 @ 03:30 PM - 04:30 PM
Conferences, Lectures, & Seminars
Speaker: Stephanie A. Coronel, Sandia National Laboratories
Talk Title: Ignition Dynamics of Reactive Gaseous Mixtures
Abstract: The study of ignition dynamics is important for a wide range of safety,environmental, and transportation applications. This talkpresentsexperimental and numerical investigations of the processes leading to ignition of reactive gaseous mixturesin the presence of ignition sources-”specifically, hot surfaces and compressive devices. Anovel experimental techniqueis presented whichgeneratesrepeatable high-temperature particles that can be injected intoa reactive environment. An interferometer that makes useof large-angle dual birefringent prisms performshigh-speed temperature imaging of the particle injection and subsequent ignition and flamepropagation of the reactive gas. The interferometer is a combination ofa differential and Mach-Zehnder interferometer and is highly stable in aninfinite fringe configuration. Numerical workanalyzesthechemical kinetics of a reactive gaseous mixture adjacent to a hot surface.A simplified expression of the thermal boundary layer growth is presentedbased on a variation of the Rayleigh problem; the use of a simplifiedexpression rather than three-dimensional calculations allows us to use adetailed chemical kinetic mechanism to simulate the chemistry while stillsaving on computational cost. Lastly, a novel experimentfor compression ignition testing of reactive gasis described. The experiment makesuse of a water column rather than a solid piston to compress a pocket ofreactive gas. The compression process leads to the formation of a multi-phase mixture consisting of reactive gas, water droplets, and water vapordue to the development of Richtmyer-Meshkovand Rayleigh-Taylor instabilities. Hydrocarbon-air and hydrogen-oxygenreactive mixtures are used in these investigations to simulate potentialexplosion hazards in the aviation and nuclear sectors.
Biography: Stephanie Coronel is a postdoctoral appointee at Sandia NationalLaboratories working in the Energetic Materials Dynamic & Reactive Science Department. Her research broadly focuses on abnormal thermal response of energetic materials as well as diagnostic development. Prior tojoining Sandia, she was a postdoctoral scholar at GALCIT (Caltech). She received her Ph.D. in Aeronautics from Caltech in 2016, where she workedfor Professor Joseph E. Shepherd on experimental combustion in the Explosion Dynamics Laboratory. She received her B.S. in Aerospace Engineering from the University of Texas at Arlington in 2009 and an M.S. inAeronautics from Caltech in 2010. Her Ph.D. research focused on experimental and numerical ignition in thermal boundarylayers.
Host: Dan Erwin
More Information: StephanieCoronel-Seminar-2019-04-05.pdf
Location: Vivian Hall of Engineering (VHE) - 217
Audiences: Everyone Is Invited
Contact: Dan Erwin