Set up of a Schlieren Flow Visualization Device

Abstract

For many people seeing means understanding because it is the most direct way of verifying. Thus, seeing phenomena into transparent media represents a challenge which needs to be solved. The schlieren technique is a method that allows to see changes in the refractive index of transparent materials when a density gradient is established. In this paper a schlieren visualization device will be put together and characterized. Di erent arrangements were assembled in order to discuss which is the optimum setup. Several aspects as type of light source, focal length or knife- edge cuto are taken into account. Ultimately, the device was tested in extreme conditions when it was used to visualize a sound wave produced by an electric spark. This allowed us to determine its speed and, therefore, corroborate that the visualized perturbation indeed corresponds to a sound wave.