Asian Journal of Physics Vol 31, No 8 (2022) 823-832

Simultaneous schlieren and shadowgraph visualization of fluid flow using one color CCD camera

A Martinez Gonzalez1, and D Moreno Hernandez2
1Depto. de Ingeniería Robótica, Universidad Politécnica del Bicentenario,
Carr. Silao – Romita km 2, San Juan de los Duran, C.P. 36283, Silao, Guanajuato, México.
2Centro de Investigaciones en Óptica A.C., Loma del Bosque 115,
Lomas del Campestre, CP 37150, León, Guanajuato, México
This article is dedicated to Professor Cesar Sciammarella

Fluid flow analysis, where its behavior is highly unstable, requires information from different optical methods to validate the observables. Usually, this task is carried out by implementing different optical setups, and the visualization of the flow. However, the complexity of these systems makes their implementation a challenge. Therefore, to facilitate the study of this fluid flow phenomenon with more manageable optical systems, we propose a z-schlieren setup that allows simultaneous recording of horizontal and vertical sensitivity schlieren images and shadowgraph images. The optical system employs two ultra-thin filters, an RGB Light Emitting Diode (LED), and a color digital camera. The performance of the optical system is demonstrated by visualizing different fluid flows. The results of this study show that shadowgraph images are contaminated with the crosstalk effect, and correction against it was applied. The data obtained is significantly improved over the existing standard schlieren methods. © Anita Publications. All rights reserved.
Keywords: Schlieren, Shadowgraph, Ultra-thin filters, Crosstalk.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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