A NEW SHADOWGRAPH TECHNIQUE FOR THE OBSERVATION OF CONICAL FLOW PHENOMENA IN SUPERSONIC FLOW AND PRELIMINARY RESULTS OBTAINED FOR A TRIANGULAR WING

摘要

A new shadowgraph technique for the observation of conical flow phenomena in supersonic flow is presented. The particular advantage of this technique over conventional types of shadowgraph or schlieren systems is that it permits observation of the conical flow phenomena in a plane normal or nearly normal to the axis of propagation. The prin¬ciple of the shadowgraph is utilized by superimposing a conical light field upon a conical flow field in such a way as to project the shadow¬graph on a propeller screen within the test section of the tunnel. Preliminary results are presented for a triangular wing of 380 half-apex angle.