Visualization of gas flows through use of IT-144 interferometer

The use of the IT-144 mirror shearing interferometer for the visualization of gas flows is discussed. An experimental set-up for obtaining a streamline spectrum in the light reflected from an aerodynamic model is presented, and the streamline distribution obtained for a flat plate with a pointed leading edge and a reflecting surface to which two wedges are attached in a flow of free-stream Mach number equal to 5 is illustrated. Means for the application of the IT-144 interferometer to the stereoscopic visualization of a three-dimensional gas flow are also discussed, and a stereoscopic pair of interferograms is presented which shows that the shock waves from the wing flaps of a supersonic aircraft model are located in a different plane from the nose shock waves.