(I think I figured out why this did not go - trying again, fingers crossed.)
> John,
>
> For my money, make the fatest part at about 60+%. The positive pressure
> gradient will (IMHO) help to keep the airflow laminar. For sure it is
> going
> to go turbulent when the pressure gradient reverses (body starts
narrowing).
> Turbulent flow skin friction (as I know you know) is many times the
laminar
> flow friction, so the less area with turbulent flow the better -
>
> But, you gotta be smooth. Any roughness or protrusions can prematurely
> trip the air to turbulent flow. I'm going to be out for a couple of days
> but
> would love to discuss this further. (And, I'm prepared to be wrong!)
>
> Thanks,
> Jim W.
>
> >Date: Fri, 7 Jan 2005 23:38:02 -0500
> >From: "John Burk" <joyseydevil@comcast.net>
> >Subject: Aero Revelations
> >
> >While reading my "Theory of Wing Sections" today I found a couple of
things
> I
> >didn't realize - (1) A streamlined shape that's widest in the middle has
> the
> >least drag (always thought the best was fatest at 30% with a more gradual
> >taper in the back) - (2) A streamlined shape that's 2 ft wide has less
drag
> if
> >it's 10 ft long than if it's 20 ft long - Less surface with 16 deg. taper
> is
> >better than more area and 8 deg. taper - Anybody disagree with these
> things -
> >John
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