Flo-Viz

[strad]

FLo-Viz is a type of paint that allows you to observe the air flow...Man I wish they would have had this stuff 30 or 40 years ago.
Short video from FP2
http://www.stradsplace.com/VIDEOS/flo-viz.wmv

[strad]

Well...I think the stuff is cool.

[Jeffsvilleusa]

That's pretty cool. I read in F1 racing a long time ago that teams used to attach pieces of cotton to their wings to try to determine similar information, though not sure why- does cotton have 'memory' in that it remains in the shape that it is pushed into?

That commentator is really pen-happy in that clip

[machin]

The idea is that you attach a load of short cotton/Wool strings to the surface of the car and then take photos of the car at the speeds you're interested in.. the wool will lie in the direction of flow, allowing you to see the flow pattern over the car....

Also, if the wool is blurred in the photo you can see that flow is unsteady in that area....

[marcush.]

I don´t get the hype about this.
Wasn´t this done for decades ? As an engineer you are looking for solutions to the issues you have .If it makes sense to throw a shovel of dust at you car at speed after coating it with a spill of light oil ..you might try it ...I could imagine people in the paddock invented similar methods of flow visualisation long ago..

[strad]

There have been other methods, but none so clear and easy to use.

[flynfrog]

you can make your own with Kerosene and cabon black.

[strad]

sure thing

[autogyro]

Unfortunately flow viz only gives one result a general image of the airflow through what ever speed and flow angles the car component has experienced.
It does not give a dynamic image through video coverage of all the seperate flow conditions like 'wool' tufts or smoke does.
It is however, a quick and convenient method of getting a rough idea in the field.

[747heavy]

you can make your own with Kerosene and cabon black.

Flynfrog is quite right,
if you fancy the flourescent look, you can use flourescent dye powder instead of carbon black, which is maybe a bit difficult to see on black/natural carbon parts.

If you are lazzy you just get this and mix it with your Kerosene aka Parrafin, and off you go.
The main reason for the use of flourescent dye is that in windtunnel testing you can use ultra violett/black light to take pictures and get a better contrast to the background.

It looks cool, but it´s not magic (but helpful), try it if you don´t believe it.

[Ciro Pabón]

Thanks, very interesting.

Well, I know Schlieren (that is, streaking).

[flynfrog]

you can make your own with Kerosene and cabon black.

Flynfrog is quite right,
if you fancy the flourescent look, you can use flourescent dye powder instead of carbon black, which is maybe a bit difficult to see on black/natural carbon parts.

If you are lazzy you just get this and mix it with your Kerosene aka Parrafin, and off you go.
The main reason for the use of flourescent dye is that in windtunnel testing you can use ultra violett/black light to take pictures and get a better contrast to the background.

It looks cool, but it´s not magic (but helpful), try it if you don´t believe it.

or buy off road diesel with the dye in it that's what I did.

this book has a pretty good chapter on how to read flo viz

http://www.amazon.com/Leading-Edge-Engi ... 0837608600