Schlieren measurement of ‘normal-spanwise length’ of a bifurcated normal shock wave in a rectangular duct

• Published in: Experimental thermal and fluid science Vol. 96; pp. 43 - 47
• Main Authors: Vaisakh, S., Muruganandam, T.M.
• Format: Journal Article
• Language: English
• Published: Philadelphia Elsevier Inc 01.09.2018; Elsevier Science Ltd
• Subjects: Aerodynamics; Bifurcations; Ductwork; Focusing Schlieren; Inclined Schlieren; Measurement; Normal shock waves; Shock; Shock waves; Supersonic flow; Temporal variations; Three dimensional shock wave; Supersonic flow; Inclined Schlieren; Three dimensional shock wave; Focusing Schlieren
• ISSN: 0894-1777; 1879-2286
• DOI: 10.1016/j.expthermflusci.2018.02.024

•Schlieren beam perpendicular to flow leads to loss of data in spanwise dimension.•Inclining the schlieren setup with respect to span gives spanwise information also.•Projection of spanwise data can be used to extract spanwise length of normal shock.•Focusing schlieren is used to verify that the method works with good accuracy. Focusing Schlieren technique is used to measure the span-wise length of the bifurcated normal shock in a rectangular duct. This is done by inclining the Schlieren setup by a small angle to the regular schlieren light path. The projection of the normal plane of the shock can be seen in the images, and can be used to deduce the spanwise length of the shock. The measurement is further verified by traversing the focusing schlieren setup to mark the physical distance between the ends of the normal part of the shock. This is the first reported work of measurement of spanwise length of a normal shock in a duct, and its temporal variation.