Localized aerodynamic flow checking

[Floordford]

Has anyone thought of a way to see how much better a specific area on a vehicle flows air at home? My first thought goes to string, tape and a huge shop fan. This way you could be out of your car and see how the air is flowing.

This thought came to me as I was thinking of air flow over my windshield wipers, side mirrors, front tires and my recessed fog lights. I want to make low profile Lexan covers to blend with the bumper to smooth over the pocket caused by my sunk in fog lights. And Id like to see the characteristics of air flow over specific areas.

Anyone done this kind of testing?

[ChazInMT]

Hey Floor, good question. I think you'd find you need many large fans and some way of making the flow smooth to have a homemade wind tunnel. We're talking a very large building, several hundreds of horsepower in fans and complex air handling, far beyond the reach of most folks who wanna test little changes.

Moreover, your questions seem to ask what you can do in the front of your car to make it more aerodynamic. It is a common misconception that the front being smoother will net you real gains in aerodynamic performance. However, the nooks and crannies are not what to look for in front, and your biggest gains are in the rear of the car in controlling how the air leaves your car.

The big picture in front is trying to get as much air as possible over the top of your car, and being stingy with what goes in the radiator. Smoothing over lights & such will not be very beneficial since the air sort of forms its own aero shape in front of these features. What car are we talking about? Hope these rambling thoughts help.

[Floordford]

My car is a 2000 Mustang. There are spots id like to experiment with like the areas of my fake side scoops, wipers, where the hood hangs over the headlights, the spot near the C-pillar and testing a spinning rim. Don't worry im not going to tape string to the spinning rim.

[Bill in Houston]

you know, just for funsies, you could use a leaf blower and a water mist and see if you can see anything happening. i mean, why not? sure, a real wind tunnel would be better, but i don't have one...

[Joenavy85]

Originally Posted by Bill in Houston

you know, just for funsies, you could use a leaf blower and a water mist and see if you can see anything happening. i mean, why not? sure, a real wind tunnel would be better, but i don't have one...

not a bad idea, since he's only doing specific area, that and the leafblower would give sufficient velocity.

[Floordford]

I have a big 30' shop fan and a floor dryer style fan. I would think they would be big enough.

[Joenavy85]

30' or 30"??

[Bill in Houston]

Originally Posted by Floordford

I have a big 30' shop fan ...

That's big enough!!!

[Joenavy85]

i suspect he meant 30", which is why i asked. But if he does have a 30' fan, he definitely has enough room to set up straightening vanes and associated equipment for a wind tunnel

[Bill in Houston]

Originally Posted by Joenavy85

i suspect he meant 30", which is why i asked.

Is anyone else thinking of that movie, "This is Spinal Tap"?