Density field of supersonic separated flow past an afterbody nozzle using tomographic reconstruction of BOS data

Background-oriented schlieren (BOS) techniques

“…In this case, the transform algorithm rebuilds the density field from ray deflections. This has been shown, for example, by Venkatakrishnan (2005), Venkatakrishnan and Suriyanarayanan (2009) and Sourgen et al (2004Sourgen et al ( , 2012. Kindler et al 2007 applied the tomographic reference-free BOS method for the study of rotor blade tip vortices.…”

Time Evolution of the Density Field of a Micro–Explosion Using Background Oriented Schlieren

“…The reader is referred to Venkatakrishnan and Meier [5] for a derivation of the reconstruction function. The reconstruction of the entire field is achieved by inverse tomography [6]. …”

Review of background oriented schlieren and development for ballistic range applications

“…Diagnostics of flows in supersonic and hypersonic facilities by BOS has been carried out in references [22][23][24][25][26], while in references [27][28][29] BOS has been used in the outdoors, with a large field of view. Several improvements of the technique are proposed, mainly in obtaining 3D measurements by tomographic imaging, [30][31][32], or by increasing the accuracy through colored backgrounds, [33].…”

“…D ps is the distance from the location of pixel shift, H[N] is the step function, SFRW is the step function response width, and IW(a) is the interrogation window, with a being its value in pixels. For IW (32,16,8), multipass evaluation was carried out. of dots.…”