The NACA vents do not create a vacuum. They only permit the flow of air from
high pressure to low pressure. They are a low drag opening only when going
---From high pressure, high volume to low pressure. Installing them as exhaust
where there isn't drag problem isn't helpful nor does it improve the flow as
exhaust is a low flow situation as well. They are Not designed for this
application. Sure they might look nice but they are actually impeding the
exhaust flow over an extractor type port.
----- Original Message -----
From: "Fergus Kyle" <VE3LVO@rac.ca>
Subject: Europa-List: NACAs backwards
>
> Fergus Kyle wrote:
> >To: <europa-list@matronics.com>
> >Subject: RE: NACA vent placement (was RE: Europa-List: Gel Coat)
> >
> >
> >|
> >| THEY ARE INSTALLING THE VENTS BACKWARDS AND IT CREATES A VACUMN
> >
> >Well, mebbe, but so does a hole if properly installed.
> >What is the inprovement in airflow of a reversed NACA duct over a simple
> >hole (for the expense)?
> >Ferg
>
> Ferg,
> My estimate is that it will simply look better and, sometimes, that's
> enough... ;)
> Rocketman -
>
> Well, I quite agree. I never even thought of that - just figured NACA had
a
> particular cause in mind. The flow behind the design is brilliant.
> Cheers, Ferg
>
>
|