Re: Aerodynamic obsessiveness

From: <dgbj_at_aol.com>
Date: Sun, 28 Jan 2007 04:46:14 EST

I wondered whether at this very low aerodynamic scale there are any vortices
behind the wing posts.

According to Van Dyke, "An Album of Fluid Motion", Figure 46 on page 30, the
flow pattern transitions from steady to oscillating at around R = 41.0. A
1/16" wing post at 2 feet per second has a Reynolds number of about 65.

Putting film between the wing posts might create more friction drag than it
eliminates. You would presumably still have a wake behind the rear post.
Might it be better to streamline the posts?

The obvious way to get an answer is to try it. Replace the prop with an
equivalent weight of clay and glide test.
Received on Sun Jan 28 2007 - 01:46:33 CET