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Group,
The problem with submerged inlets, and Buly is correct to mention that
means flush with the surface, is that they do not handle back pressure well. Ed
A posted the original NACA data and their conclusion was that submerged inlets
don't work well with RADIATORS. The comments PL has been making are only to
re-publish the data. If you do a smoke tunnel test on submerged inlets you will
find that once enough pressure is built up they will "flip" and hardly take in
any air at all. The actual NACA ducts also have the carefully designed lips, or
rounded edges to train the boundry layer into the inlet. The full profile
defined by the NACA is rarely used. Most of the inlets we see are some attempt
at looking like a NACA inlet, without the trouble of actually BEING a NACA
inlet. We used to call this "eyeball engineering." Aircooled engines do work
better with NACA inlets as there is less pressure differential than with a
radiator. This doesn't mean they will never work, just that the NACA didn't
recomend their use with a radiator/heat exchanger.
Bill Jepson
In a message dated 3/9/2006 8:24:30 PM Pacific Standard Time,
atlasyts@bellsouth.net writes:
John,
would you stop calling it a NACA scoop. Remove the big raised
lip
and make it flat. Than come and report to us. Your inlet is half
submerged and half raised scoop. NACA is a flush with the surface
SUBMERGED inlet.
Buly
On Mar 9, 2006, at 10:44 PM, John
Slade wrote:
> Dave,
> My only cooling intake is the plans
Cozy IV NACA.
> Cooling has never been a problem.
>
Regards,
> John
>
> David Staten wrote:
>> At the
risk of invoking PL's name, anyone else read this months
>>
Sport Aviation mag from EAA, and notice an article on cooling that
>> seems to indicate that NACA's are acceptable and adequate
for
>> aircraft cooling needs? I have no idea regarding the
authors
>> credentials, and I no longer monitor PL's
"newsletter".. I was
>> curious more than anything else...
Pauls reaction, others
>> reactions,
etc.
>>
>> Translation.. yes.. I'm stirring the
pot/Trolling... I figure if
>> we are using NACA's on the
Velocity, that makes us somewhat of a
>> NACA
supporter..
>>
>> Dave
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