1. Experimental set-ups (materials and methods)

1.1 Light sources

In fluid mechanics imaging, illumination is one of the most important elements, as it reveals and/or quantifies the physical phenomena being studied.

Light sources are characterized by their luminous flux, spectral range, chromaticity, characteristic time and geometry. The physical phenomena to be characterized (fluid properties, flow structure and velocity, etc.) influence their choice. Of all potential light sources, the most widely used today are lasers (generally monochromatic) and LED arrays (multi-wavelength white light).