| ----- Original Message -----
| From: "qcbccgalley" <cgalley@qcbc.org>
| To: <europa-list@matronics.com>
| Subject: Re: NACA vent placement (was RE: Europa-List: Gel Coat)
| | NACA vents are INlets not outlet vents. They don't work as outlets.
|
| Right. I've noted several mentions of using the vent for evacuating the
| cabin air. The NACA inlet was chosen to operate the engine inlets for the
| F93 version of the Sabre. It is designed to induce intake from high speed
| flow without incurring great drag. . It will do nothing for cabin outlets
or
| any other reverse flow. Might as well cut a hole.
| Ferg
| A064
Europa-List message posted by: "Rob Housman" <RobH@hyperion-ef.com>
| While I must agree with your comments, Ferg, there is a way to use the
NACA
| inlet to do the job, thanks to our old friend Bernoulli. See
| http://hyperphysics.phy-astr.gsu.edu/hbase/fluids/aspir.html for a brief
| description of an aspirator, a device for generating low pressure by using
| higher pressure flow. Many of us are probably familiar (from chem lab)
with
| the scheme shown in the hyperlink where water is used to generate air flow
| into the tee, but the same principle works with compressed air in the
| straight leg of the tee to create a vacuum in the side arm of the tee.
| Clever guy, Bernoulli.
| Best regards, Rob Housman
| Europa XS Tri-Gear A070
Rob et al,
I'll buy that, so I went to the site and saw three choices:
Hyperphysics - to 'Condensed Matter'[the only applicable site]; then
Mechanics - to Pressure to Kinetic Energy; then
to Potential Energy; then
to Bernoulli Equation -
much of which I remember (if not with fondness), but little of which
inspired understanding of how a NACA inlet is sited/configured to extract
cabin air at relative low speed. Perhaps there's a site therein which I
missed.......
There's just the off-chance my comprehension is ready for a cleaning
and polishing, but can you point me to the principle or practicality of
using a NACA inlet design?
Of course this is all E&OE,
Cheers, Ferg.
|