Airborne Background Oriented Schlieren Technique

NASA has developed a novel method to render visible the density changes in air that cause a refractive index change by an airborne vehicle. These density changes include shock waves, vortices, engine exhaust, and wakes. The determination of location and strength of shock waves and vortices is fundamental to understanding the flow around an aircraft. These features are strong enough to affect the environment that the vehicle inhabits; for example, they can cause drag and/or produce undesirable noise. The researcher must be able to predict and mitigate the effects of these flow features.