[Piwoslaw]

Originally Posted by jim-frank

I was out in the eastern plains of Colorado last week and took advantage of the stady 30+ mph winds that were blowing. They were very consistent in both direction and speed, so I parked my car facing into the wind and used a roll of masking tape and some yarn to make a tuft panel on the back window of the car. The results were pretty clear, in that the flow was smooth and attached along the top of the car, detaching about two inches down from where the window starts sloping down.

Using steady wind for tuft testing is a good idea. You can't change the speed, but you can do things you normally wouldn't be able to when tuft testing on the highway, like get out and look from different angles. Another is tuft testing the windshield, which probably can't be "tufted up" when the vehicle is moving on a public road.