High-Bandwidth High-Resolution Sensor for Hypersonic Flows

There is the need for new diagnostic instrumentation capable of detailed hypersonic flow field characterization with spatial resolution of order 1 mm3 and temporal bandwidth of order MHz. In this proposal Princeton Scientific Instruments, in collaboration with the Ohio State University Gas Dynamics and Turbulence Laboratory, offers a novel solution based on PSI's recently developed Ultra High Frame Rate CCD Imager, in combination with a "burst mode" laser source developed by OSU. The proposed program focuses, primarily, on hypersonic flow diagnostics based on Planar Laser Induced Fluorescence (PLIF) imaging of the nitric oxide (NO) molecule, which, because it is a gas at temperatures as low ~ 75K, is readily seeded into even hypersonic flow facilities. We have demonstrated, in Phase I, the potential of a new NO-PLIF MHz frame rate velocity imaging diagnostic, termed Planar Doppler Fluorescence Velocimetry (PDFV). In Phase II we will continue to develop quantitative imaging diagnostics, culminating in a demonstration of the practical utility of the system by performing measurements in the AFRL - Air Vehicles Directorate Mach 5 Hypersonic Wind Tunnel. The proposed instrument system will also serve as a flexible diagnostic tool, capable of density and temperature imaging at frame rates as high as 1 MHz, and more conventional measurements, such as focusing Schlieren, Shack-Hartman wave front sensing, and holographic interferometry, at even higher frame rates.