A balsa-dust technique for air-flow visualization and its application to flow through model helicopter rotors in static thrust

Marion K. Taylor
Nov 1950

A method of visualizing air-flow patterns by observing the motion of finely divided particles of balsa wood introduced into the air has been developed by the National Advisory Committee for Aeronautics. The technique is simple to use and requires only a supply of balsa wood, a camera, and photographic lamps.

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