Aerospace & Mechanical

Seminar Announcement

Advancement of Non-Intrusive Optical Diagnostics for the Study of Supersonic Aerothermodynamics

Christopher S. Combs

Research Assistant Professor

The University of Tennessee Space Institute
Tullahoma, TN

The continued development of non-intrusive diagnostics will be critical to the advancement of the state-of-the-art in high-speed aerodynamics research. Realizing the high-speed capabilities that have become an elevated national priority such as sustained hypersonic flight, atmospheric reentry, commercial supersonic flight, and air-breathing propulsion will require measurements at high-speed and high-enthalpy conditions that are currently difficult or impossible to make. Moreover, measurements in high-enthalpy and reacting flows are in increasing demand given the DoD’s push for research in hypersonics. Recent advances in imaging and laser technology—such as cheaper high-speed cameras, development of plenoptic cameras, and advances with pulse-burst lasers—have increased the potential capabilities for non-intrusive diagnostics. Considering the recent strides made in the development of non-intrusive diagnostics and the current measurement challenges faced by the experimental community, there is a need for researchers to leverage the recent advances in imaging and laser technology to develop the next generation of game changing non-intrusive diagnostics that will drive the next fifty years of high-speed aerothermodynamics research. Here, a review of recent diagnostics developments at The University of Texas and The University of Tennessee Space Institute will be presented, including an overview of the naphthalene planar laser-induced fluorescence technique—a diagnostic used to explore ablation physics by investigating scalar transport due to sublimation in supersonic flows. Results from an investigation of the Orion Multi-Purpose Crew Vehicle reaction control system jets using NO planar laserinduced fluorescence will be shared, as well. Lastly, data will be presented from research on the dynamics of transitional shock-wave/boundary layer interactions collected using a variety of measurement techniques.

Christopher Combs received his B.S. in Mechanical Engineering from the University of Evansville in Evansville, IN in 2010 and completed his Ph.D. in Aerospace Engineering at The University of Texas at Austin in 2015. His primary area of research interest is laser diagnostics applied to supersonic flows and his research in the application of PLIF to characterize low-temperature ablation was supported through NASA’s Space Technology Research Fellowship program. Dr. Combs joined the faculty at UTSI for the Fall Semester of 2015 and has been leading the development of diagnostic capabilities within the UTSI High-Speed/Hypersonics initiative, HORIZON (High-speed Original Research and Innovation ZONe). Dr. Combs’ research has been funded by multiple government agencies including NASA, AFOSR, ONR, AEDC, TRMC/HSST, and DARPA and he is a current member of the AIAA Aerodynamic Measurement Technology Technical Committee.

Wednesday, February 15, 2017
3:30 PM
Seaver Science Library, Room 150 (SSL 150)

Refreshments will be served at 3:15 pm.