Scale wind tunnel model testing

[98ciHemi]

Has anyone here tried anything like this? I am considering trying to make a 1:16 scale clay Escort so that I can play with different aero stuff. I have limited access to a small windtunnel, and I have done wood sculpting before, so I believe that I could make a pretty decent model. Would this be an accurate way of testing? The way the wind tunnel is set up now it measure only lift and downforce, but I may be able to make it measure force inline with the car if I work on it. I also may be able to bum a fog machine to judge airflow. Any thoughts?

[DanStokes]

Re: Scale wind tunnel model testing

A couple of lads from Dayton Ohio had pretty good luck with this syatem. Their tunnel is now in Dearborn, MI. It's a perfectly viable method but is only as good as the instrumentation and your ability to accurately scale the car and the measurements. POST PICS!

Dan

[Monster]

Re: Scale wind tunnel model testing

Sounds worthwhile Walt, go for it and report back here on your results.
;)

[DanStokes]

Re: Scale wind tunnel model testing

Anyone have a model of a '78 Camaro lying around? I'll send it off to Walt.

[98ciHemi]

Re: Scale wind tunnel model testing

Gimme the track widths, wheelbase, tire size and wheel size and I will start working on a base for it. My plan right now is to form the bulk of the car with pine or basswood, and then lay up clay around that. To measure the drag, I will make a small air cushion table sort of like an air hockey table to get eliminate surface friction, and then use my airbrush compressor as an airpump. the car will go on a base that will ride on the air cushion and then be held back by a light rubber band. I can use a powder scale to establish the rate of the rubber band, and then use a scale to measure rearward movement of the car, and hence measure the drag of the car. If that makes sense to anyone. Downforce is easy, and just requires fixing the car to a kitchen scale and sticking it in the wind tunnel.

[98ciHemi]

Re: Scale wind tunnel model testing

A couple of lads from Dayton Ohio had pretty good luck with this syatem. Their tunnel is now in Dearborn, MI. It's a perfectly viable method but is only as good as the instrumentation and your ability to accurately scale the car and the measurements. POST PICS!

Dan

And those lads you speak of were losers. Hmmph. Bicycle mechanics.

[Monster]

Re: Scale wind tunnel model testing

Anyone have a model of a '78 Camaro lying around? I'll send it off to Walt.

Umm, Dan, I know you have a Camaro, but Walt has an Escort.
He wants to check out different aero stuff on HIS car.

So, if anyone has a 1:16 scale Escort model lying around, sent it to Walt.
;)

[studemax]

Re: Scale wind tunnel model testing

Keep in mind you can do aero testing in water, too.
Since water is denser, you can get good results at lower speeds.
Just an idea, if you'd like to follow it.

[98ciHemi]

Re: Scale wind tunnel model testing

Hadn't thought of that. Air seems a little easier since I already have a windtunnel. I may keep that in mind though.

[greenjunk]

Re: Scale wind tunnel model testing

It was my intention to do something similar to this and test a model of my camaro in it to see if I can replicate the results I learned in a real tunnel. seems like if you built your own tunnel with a couple digital meat scales you could get some sort of results assuming you had the fan to pull it.

[fahrenschnell]

Re: Scale wind tunnel model testing

Walt.....You never cease to amaze me.....Go for it.

Seth

[squirrel]

Re: Scale wind tunnel model testing

lmao...neat idea!

http://cgi.ebay.com/ws/eBayISAPI.dll...m=190343410833

[Monster]

Re: Scale wind tunnel model testing

Good catch Jim.
Not sure if the 1/18 size will be a factor, but it is a 1984 Ford Escort RS 1600i Diecast model car ...

[98ciHemi]

Re: Scale wind tunnel model testing

That would sort of work, after removal of the spoiler and the front fascia. The U.S. spec Escorts used a different front end design. The Escort shown there had a stock drag cooefficient of .38. Not sure how good that is, but it gives me an idea where I am at.

I cut out my wooden base last night, and now I am putting wooden blocks together to form the bulk of the body. I will take pics of the base when I have it put together.

[Monster]

Re: Scale wind tunnel model testing

Walt, yeah ... with the model being diecast metal, kinda makes it hard to modify it.
I am really interested in the progress and eventual outcome of this project.
Keep us updated as you move along.
;)