Schlieren photography for visualizing turbulence

[Coyote X]

Some Background:

Schlieren - Wikipedia, the free encyclopedia

Schlieren flow visualization is based on the deflection of light by a refractive index gradient. The index gradient is directly related to flow density gradient. The deflected light is compared to undeflected light at a viewing screen. The undisturbed light is partially blocked by a knife edge. The light that is deflected toward or away from the knife edge produces a shadow pattern depending upon whether it was previously blocked or unblocked. This shadow pattern is a light-intensity representation of the expansions (low density regions) and compressions (high density regions) which characterize flow.

the picture clearly shows air currents, it isn't using smoke it is actually showing varying air density

Schlieren Optics -- this page shows the standard way of building the setup and some pictures at the bottom of the page showing examples of what it can do.

So seeing as how this would be pretty easy to use to find turbulence and experiment with lots of aero stuff, does anyone currently use this anywhere? If I had a scale model of my car I would really start building this system and get some cool videos. There is a ton more of information on Schlieren imaging and I am still hunting around but I figured I would at least post this on here and let everyone else see it.

Pearson - Science News this link has a really neat picture of a shock wave from a plane halfway down the page.

[aerohead]

I've only seen it used in ballistics research where shockwaves were inspected.I have to admit that I never considered doing it.I thought that perhaps,the target passed through a gate,with projecting screen behind,and the optics of the camera were pre-focussed on the screen,to capture the" shadow" of the "air",at varying density behind the target vehicle, cast by the sunlight shining across the void in between.Hmmmmmmmmmmmm!

[COMP]

many years back we set of smoke bombs at the end of a track to see what our drag car did,,,,it was tough to see ,we only had still camera's

[aerohead]

Originally Posted by COMP

many years back we set of smoke bombs at the end of a track to see what our drag car did,,,,it was tough to see ,we only had still camera's

Smoke grenades add to the excitement!