Wavefront — Department of Defense STTR Phase I: Non-invasive methods are required to measure the turbulence in supersonic jet plumes in 3-

Description

Non-invasive methods are required to measure the turbulence in supersonic jet plumes in 3-D with high temporal and spatial resolutions. The turbulent supersonic jet plume changes rapidly both in space and time, and hence any viable approach must acquire the entire 3-D velocity field at even faster speed for comparison with the temporal and spatial velocity field solved in Large Eddy Simulations. Unlike conventional LIDAR scanning techniques, which cannot scan through the entire 3D volume of the jet plume fast enough, and also unlike particle imaging velocimetry, where added invasive"seeds"are required, the proposed Micro-Plasma Turbulence Velocimetry (uPTV) is designed to deliver simultaneous imaging of the entire turbulent of the jet plume without added seeds. A photon-counting imager is concurrently under development for optimal uPTV. During Phase 1, we will setup uPTV system, demonstrate uPTV concept on a limited-scale wind tunnel, and correlate the stereoscopic image data. The prototype is readily deliverable. In Phase 1 Option and Phase 2, we will construct, test and optimize a full-scale fieldable uPTV system for a typical jet plume, in laboratory setting, at the hanger and on the airfield, for delivery to DoD laboratory.