Density measurements using the Background Oriented Schlieren technique
نویسندگان
چکیده
This paper describes the implementation of a novel technique called Background Oriented Schlieren that can produce quantitative visualization of density in a flow. This technique uses only a digital still camera, a structured background, and inverse tomographic algorithms which can extract two-dimensional slices from a three-dimensional flow. This has been applied to obtain the density field for an axisymmetric supersonic flow over a conecylinder model. Comparisons with cone tables show excellent agreement. List of symbols b wave angle h viewing angle q density (kg/m) k wavelength (m) e angle of deflection D diameter of cylinder f focal length of imaging lens G(k) Gladstone-Dale number j ffiffiffiffiffiffi
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