Tufting the Prius
When I first started this blog, I wrote a post on tuft testing which turned out to be one of the more popular articles here. I covered the basics of tuft testing but recently thought I could write a little more about how to interpret tuft behavior and what this looks like in the real world. This article will demonstrate how to set up a tuft testing session, how to get usable results, and how to start analyzing them. Setup As I wrote before, tuft testing is cheap and easy; all you need is yarn, tape, and a camera. Your tufts shouldn’t be too short (they won’t show up well on camera) or too long (long, flapping tufts will give you less resolution in the airflow patterns). I like to hold a length of string between my second and third fingers, stretch it across my hand, and then cut it near the thumb: This gives me pretty consistent 60-70mm tufts—long enough to be visible to a camera some distance away. Once you have your tufts cut, tape them to your car. You can use long strip