An optical method of measuring flow velocity in an arc-heated wind tunnel

Abstract

An optical method has been devised to measure velocity in the flow from an arc-heated wind tunnel. This method does not require the knowledge of any flow condition, and it does not interfere with the flow. Velocity measurements have been made in the flow from the University of Southampton arc-heated wind tunnel using this technique. These results have been compared with the results of a Langmuir probe survey made under the same conditions, and it has been found that they lie within the uncertainty of the Langmuir probe data. Refinements to the apparatus are suggested.