Areodynamics Question

[VectorOne]

Hey guys, I have a question regarding areodynamics on a F1 in schools car. Our team is in debate over paint styles, In the past we have always used a very high quality smooth finish. But we have recently found a very unqiue paint that has not ever been tried on an F1 car. The finish of this paint however is rough (simular to a 600 grit sandpaper) I believe that this paint will create the same effect as a golf ball, creating a layer of air around the car? We have tried to test both kinds of paint on the cars but we are having troubles getting an accurate average. Do you guys have any idea's/opinions on a paint finish for a car?


Thank-you
Daniel VectorOne Canada

[garygph]

Have a look at this thread http://www.f1technical.net/forum/viewto ... =6&t=13419, it may help.

[Lycoming]

having dimples like a golf ball will be of benefit to you if your car is shaped like a golf ball. A golf ball is by necessity spherical. A car is not. What aerodynamic characteristics do you seek for your cars? Do spheres have those characteristics?

Also, from a purely scientific standpoint, if you cannot conclusively demonstrate that one is "better" than the other by experiment, then what good is it to say that one is "better" in theory? If your experimental method is adequate in that error bounds are tight enough and outside factors are adequately controlled, that should be the end of that. If you can't measure a difference, then that just means that within your error bounds, they're identical. If your error bound is sufficiently small, then the difference is negligible and they're all functionally equivalent.

What do you mean by "having troubles getting an accurate average"?

[thisisatest]

As stated above, dimples or other types of boundary layer disturbances are beneficial for objects whose shape, by necessity, cannot be streamlined. That said, certain parts of a car are, by necessity, not streamlined. Exposed driveshafts are one, possibly the trailing underside of a wing that has to have an angle of attack that is steeper than ideal. Benefits are also small. For instance, on bicycles, Zipp dimpled the surface of their wheels' hub shells. At 30mph for 25miles, the drag savings amounted to a 3-5second time improvement. As a side note, their ridiculously high grade ceramic bearings saved only 1-3seconds versus their extremely high quality steel bearings...

[VectorOne]

I also should have mentioned that these "Dimples" will be very small.
@Garygph Thanks for the redirect! I found something that better represents my situation because of it.

A better representation of what im doing is a Lotus effect
http://en.wikipedia.org/wiki/Lotus_effect

@Lycoming Of course our car is not a sphere, but wouldnt having this effect on certian parts of the car (ie front airfoils) decrease the amount of drag from these components?
We are having trouble gathering data due to a lack of finished cars that we can test, We've also had breakdown problems that have kept us from regluar testing

Daniel VectorOne Canada