Duncan McFadyean a crit :
>
> Why?
> The top of the cowl (towards the windscreen and away from the nose) is a
> high pressure area, whereas the sides of the cowl are low pressure.
>
>
Hi Duncan and all,
Remember, though, that one has to determine where the pressure
distribution changes from low pressure to higher pressure. What you
mention is OK at the very foot of the windscreen.
As long as the airflow accelerates, the pressure is low, and a NACA
scoop will not flow in the right sense. I know of several designs where
NACA scoops are BLOWING air instead of letting it in, to the
surprise/dismay of their builder or designer ;-)
My two cents,
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
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