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Re: Archie a non-flyer? (was:Re: origin of bats/reply 2 to TMK)

On Thu, Jun 26, 2008 at 7:29 AM, jrc <jrccea@bellsouth.net> wrote:
>> One will have problem if do not restrict flow direction in the
>> analysis - specially if consider a flow parallell to gravity
>> acceleration.
> One will have a problem if they do restrict flow direction.  With that
> restriction, you are no longer modeling what's happening to the airfoil.

Nope, since one will analyse lift here. Deviation from horizontal flow
must be translated into more or less lift - or differential pressure
over the wing faces.

>> But so let's go put Bernouilli effect in a zero-cambered wing. We will
>> regard two situations: I) positive angle of attack and II) negative
>> angle of attack. Where the air is accelerated in (I), and where the
>> air is accelerated in (II)?
> For a non-cambered wing at positive angle of attack, the leading stagnation
> line shifts away from the leading edge to a line on the lower surface near
> the leading edge, and the flow above that line reverses, accelerates
> forward, around the leading edge, and aft over the top of the wing at high
> velocity.

Why the air above the stagnation line will accelerate in (I)? And the
air bellow stagnation line will accelarate in (II)?

Roberto Takata