Images of Arc-Heated Supersonic Argon Plasma Jet Impinging on a Flat Plate

Low-density flow fields are usually difficult to visualize using ordinary optical methods. However, plasma flows, having high temperature or excited species in them, may show up some features of the flow field in a simple photograph. A dc arc-heated supersonic argon plasma jet impinging on a flat plate under low ambient pressure was photographed. The varying brightness shows features of the flow field which bear some resemblance to the results by numerical simulation of a cold argon jet impinging on a flat plate.