Imaging, Filtered Light Scattering Velocity Diagnostic

The boundary layer plays a critical role in aerodynamics, acting as a barrier to the transfer of momentum from the air to the flight vehicle. In-flight measurements of velocity fields in the boundary layer could be used to establish the transition point to turbulent flow. This Phase I SBIR project will investigate a novel method for imaging flow velocity based on filtered light scattering. It does not require seeding of the flow, and thus is suitable for in-flight tests. This approach can benbsp;implemented with diode lasers, which should result in size, weight and power compatible with installation aboard small aircraft, or in high-vibration environments such as hypersonic vehicles. The method could also be used as the basis for velocity measurements in wind tunnels or in combustion research.