[freebeard]

Originally Posted by Tugger

You see my well intentioned friend - the only difference between what you call a worthless junk kitchen table wind tunnel and a "real wind tunnel" - costing millions of dollars, are two things, size and air velocity.

The third thing is Reynolds number. Stick around and you might learn about it.

Originally Posted by Tugger

I map thermal gradients and air flows, from the stratified air layers in my own home with an incense stick.

All of the air flows, and turbulence from the delaminating boundary layers, projections etc - everything, can be tracked using an incense stick, in air velocities as low as 1/4 of walking speed.

As have I. The incense smoke dissipates at half-walking speed.

...and even an open window with a bathroom fan sucking the air into the room, through the window.

Oh, come on. That's no longer a tunnel. It does solve the problem of tunnel blockage though.

I don't know if you lurked before emitting 8 posts in 24 hours, but in case you've not found them:

http://ecomodder.com/forum/showthrea...ead-26678.html

http://ecomodder.com/forum/showthrea...els-23040.html

http://ecomodder.com/forum/showthrea...el-3432-2.html

At the scale you're working in a water tunnel is appropriate:

http://ecomodder.com/forum/showthrea...ies-31047.html