Aerospace Engineering Brown Bag Lecture Series, Featuring Catherine Liu

The October 8th Aerospace Engineering Brown Bag Series, featured AE undergraduate Catherine Liu.
Liu presented,
“Turbulence Diagnostic Methods for Flame Characterization in a Swirl Nozzle Burner"
Flame burn profiles and behavior under a variety of flow conditions is a “hot” topic in propulsion for all types of fuel injectors, especially with the increased interest in coaxial swirl injectors. While analytical models and CFD have provided a wealth of information for laminar flow, existing turbulence models leave much to be desired. Direct numerical simulations are extremely computationally expensive and limited in scope, thus it is necessary to observe real-world turbulence phenomena to characterize it. Because turbulence occurs over such short length and time scales, characterizing flame patterns and recirculation zones requires very precise measurement techniques to capture the smallest features. This presentation will discuss a few precision systems for turbulence diagnostics, including hot-wire anemometry, laser-doppler velocimetry (LDV), and particle image velocimetry (PIV), along with their respective advantages and limitations. Data collection methods and data post-processing will also be discussed for the PIV case.