[tasdrouille]

So, I've been reading a bit about wind tunnels lately, secretly dreaming of someday building my own.

So I'm reading about all this stuff, closed or open jet, corner vanes, contractions ratios, screens, honeycombs and what not to get the cleanest flow possible, and for a 200 square feet test area I'm ending up with something over 150 feet long and so tall that even if I had the money I would never get the permit to build it.

But what if someone was to make a garage sized tunnel? Something 24 feet long by 12 feet wide and 10 feet tall. Make one end with a bellmouth lip and the other end with what would be needed to move 600000 CFM. How dirty would the flow be? How meaningful would the measurements made in such a tunnel be for a common midsize car? What would be needed to move 600000 CFM?