Laser-Aided Visualizations of Complex Fluid Environments
Presenter: Jonathan Retter
Date: Friday, August 16, 2019
Location: NIA, Room 137
Time: 11:00 AM – 12:00 PM
Even as we live in an increasingly simulated world, we continue to rely on experimental observation of complex fluid flows to help guide or validate the coinciding simulations. The development of laser diagnostics over the years has led to the measurement of a variety of quantities of interest to the modeling world. While the development of these diagnostics is important on its own, the goal is always the improved physical understanding gained from the results. This talk will feature two examples of such flows where a variety of diagnostics have improved our physical understanding: (1) a plasma-assisted hydrogen diffusion flame, where the electric field induced body force dramatically alters the structure of a flickering flame, and (2) an aluminized propellant burn, where a multi-phase plume introduces various diagnostic challenges. The talk will conclude with the ongoing efforts of diagnostic development for flows reaching hypersonic speeds, including techniques for temperature, pressure, and velocity. The diagnostics discussed in this talk include those for velocity (PIV, DGV), temperature and species (spontaneous Raman, CARS, filtered Raleigh scattering), and electric field measurements (electric field induced second harmonic generation).
Jonathan Retter is a postdoctoral researcher in the Engineering Sciences Center at Sandia National Laboratories in Albuquerque, NM. He received his Ph.D. in aerospace engineering at the University of Illinois at Urbana-Champaign, where his work focused on the experimental characterization of a plasma-assisted hydrogen diffusion flame by means of nonintrusive laser diagnostics. Since graduating, he continues to employ laser diagnostics at Sandia on a variety of challenging fluid/combustion environments.