Home made wind tunnel

[onefstek]

Cd asked me to show off my home made wind tunnel.

After a good time reading and trying to find info on my car's aero, I decided to just make a wind tunnel so I can see what results I can get.

Here are some pics

Wind tunnel



Model car in wind tunnel with stock spoiler



Model car in wind tunnel with kamm spoiler



This confirms the ideas I had and could possibly help me win some races next year.

Stefan

[jakobnev]

Wait, did you just photograph a computer screen?

[onefstek]

Originally Posted by jakobnev

Wait, did you just photograph a computer screen?

I had a video that I put on the computer. Then I pause it and took a picture. A lot easier to do that then try to take a pic of the car in the tunnel.

Stefan

[BamZipPow]

In Windows, there's a button labeled "Print Screen" that will capture it to yer clipboard. Paste it into yer favorite paint program to edit.

I usually keep Google's Picasa (free) running and when I press Print Screen, it will automatically capture it to my designated folder. After I capture all the screen caps I need, I can then go into Picasa, right click on each picture, and "Save a Copy" which will automatically convert it from a BMP file to a JPG file. I then delete the original screen BMP file.

[Cd]

Thanks for posting this, but how did you go about actually creating the tunnel, what did you use for the smoke stream, and what sort of fans were used ?
You might want to look into an image capture program such as " Snagit "

[Cd]

Whuups. Sorry. I'm on my smartphone and the first image hadn't loaded yet.
Nice tunnel !
So what did you use for the smoke ?

[Cd]

I did a tuft test on our car. Here are a few images from the test.

http://www.flickr.com/photos/6037656...th/2334331320/
You can attach tiny 1/2" sections of thread to your model to simulate a tuft test. I tried it using a shop-vac on a model that i have of our car. It's fun, but pretty much useless compared to an actual test ( based on my testing )

You might try it anyways - it's interesting.

You can also tuft test small areas of your actual car by blowing air towards the section you want to test using a shop-vac. I used the shop-vac on the side glass around my rear view mirror and noticed that the tufts reacted much the same that they did in the actual test.
However, the angle is critical and i knew what i was trying to duplicate after seeing the prior test.

[onefstek]

I used a box fan in the back. As far as smoke I used incests, it works but not as good as I would like it to.

Stefan

[Cd]

Originally Posted by onefstek

I used a box fan in the back. As far as smoke I used incests, it works but not as good as I would like it to.

Stefan

Surprisingly accurate results !

Did you have it blow or suck the air past the car ? I may be mistaken on this, but it would be better to have the air pulled past the car, rather than blasted at it from the front ( straighter airflow )
You might also look into a smoke machine. You can pick one up for cheap from a discount Halloween store.
http://www.google.com/products/catal...MAI#ps-sellers

Hey, so i bet it smells really nice when you do your testing eh ?

EDIT : i see you have the fan mounted the correct way ( sucking the air past the model )

[onefstek]

Originally Posted by Cd

Surprisingly accurate results !

Did you have it blow or suck the air past the car ? I may be mistaken on this, but it would be better to have the air pulled past the car, rather than blasted at it from the front ( straighter airflow )
You might also look into a smoke machine. You can pick one up for cheap from a discount Halloween store.
Gemmy 400-Watt Fog Machine 62045

Hey, so i bet it smells really nice when you do your testing eh ?

EDIT : i see you have the fan mounted the correct way ( sucking the air past the model )

Yes fan is mounted in the back to suck the air. And yes it smelled really good. LOL

Stefan