Phil,
Thank you very much for your insight on VG's. Guess I had better wait until
after you run your simulations before adding them.
Thanks again,
Dale
----- Original Message -----
From: "flyingphil2" <ptiller@lolacars.com>
Sent: Friday, May 11, 2007 2:33 AM
Subject: Re: Europa-List: Votex Generators
>
> This is developing into quite a discussion. I'm an aerodynamicist by
> trade and so here's my answers to the points above:
>
> 1. If someone wants to try VGs on a Europa then go ahead but I suspect
> they won't make any difference. The wing design is far more advanced than
> those seen on www.landshorter.com which tend to be things like the Kitfox
> etc. VGs may improve flow over the ailerons which will make the aircraft
> feel better at slow speeds and will improve controllability near the
> stall. With a poor wing design they may reduce the stall speed. Don
> Dykins used a lot of his (and his department's) experience in the Europa
> wing and that was previously used on aircraft like the BAe 146 and early
> Airbus.
>
> 2. Graham is right about the Long Eze and the way in which the VGs
> helped. I guess the laminar region on the canards was probably the first
> 25% of the chord and there was a trailing edge separation. The Europa is
> designed to have a larger laminar region with no separation and so the VGs
> will not help in this case.
>
> 3. To reduce the stall speed on the Europa you would need to have a more
> powerful flap with maybe an additional 'flap vane' ahead of the main flap
> or something like leading edge slats. You could try a 'blown' wing as
> well if you were keen.
>
> On another point:
>
> NACA intakes are designed to be an efficient and low drag intake method.
> The edges of the intake generate small vortices which the flow down the
> intake and they work very well indeed if positioned in the right place. I
> think Duncan's issue may be down to a positioning problem and you won't
> improve the flow down that duct with a VG at high aoa if the flow isn't
> going that way in the first place. That brings me on to another point. I
> routinely run large computer simulations of external aerodynamic cases in
> my job. I'm quite keen to look at a Europa but need some CAD geometry.
> The factory doesn't have any as the moulds were hand made so my question
> is has anyone, who has too much spare time on their hands, made a good
> quality CAD representation of a Europa? I know there are some models
> floating round for flight simulators but they are far too basic for what I
> would need.
>
> Regards,
>
> Phil
>
>
> Visit - www.EuropaOwners.org
>
>
>
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