Hi, Paul....in the not too distant past, we had been discussing the best
placement of inlet/cooling scoops for the canards. I came upon this posting
on the canard aviators site. Interesting? Take care. Paul Conner
From: "Joe Dubner"
To: <canard-aviators@yahoogroups.com>
Take a close look at this and you'll know where to put your inlets".
http://home.velocitus.net/jdubner/Profile1.jpg
http://home.velocitus.net/jdubner/Profile2.jpg
--
Joe
Long-EZ 821RP
On 16-Dec-03 16:38 Art Bianconi wrote:
Graham Shevlin's post on problems cooling his Long is a source of some
frustration.
It's been close to 30 years since this design hit the runways and yet I
continue to see
repeated posts dealing with high temps. Wayne's generous effort to help
Graham is
not his first. He and others before him have addressed this issue
repeatEdly over
these many years. So why does this issue persist?
I've never seen the results of any tuft tests on the belly or the Long
or the Ese but I
am growing more and more convinced that any attempt to cool the engine
from
below the cowling is fraught with trouble. Granted, many have made it
work but the
costs in time, frustration and experimentation appear to have been high.
And they
only go to prove that if you work hard enough you can make damn near
anything
work to some degree. .
It had to be at least 15 years since I spoke to John Rontz about this
issue and while I
do not remember his exact words, I do remember him saying something
like: "Here.
Take a close look at this and you'll know where to put your inlets".
I examined the color printout he handed me and I immediately saw an air
pressure
distribution profile of the Long with red being the high pressure areas
and blue the
low or negative ones.
NOT TRUE!!!!!!!! OPPOSITE! PL
It will come as no surprise to anyone of you to know that the front of
the canopy and
the leading edges of the wings and winglets were bright red as were
other parts like
the nose of wheel pants and main gear bow. The bottom of fuselage aft of
the speed
brake had relatively low pressure. It wasn't at the aft (deep blue) end
of the pressure
gradient spectrum but it was obvious that in terms of pressurizing a
cooling inlet, this
wasn't the place!
My eyes were drawn to another bright red area of high pressure. I
pointed to the
forward part of the cylinder blisters in the top cowling, "Here?"
I do remember John smiled and nodded his head.
I've reported this any number of times at the old C-A site over the
years.Some of you
likely remember it. Some of you immediately wrote and asked for a copy
of the data
John gave me. Sorry crew. That data was lost many years ago. Perhaps if
one of you
knows how to reach John, you can convince him to make it public again.
Not that it's vital for I am confident that any of you standing in front
of a Long and
looking down the "Barrel" of it's fuselage will immediately verify what
John asserted a
long time ago. Those blisters dominate the profile drag in that area and
promise to
provide the best cooling where it's most needed: cylinder heads and
exhaust
manifold.
Armpit scoops may prove better than what the Long has now but located as
far aft as
they are suggests that the air must do a 180 to get back to the
cylinders.I am not
convinced that's the best solution.
Maybe this will help some.
Have a wonderful holiday and safe year!
Art Bianconi
aka
"Laughing Jaguar"
The trouble with this is whoever wrote it got it wrong.
Blue is high pressure and red is low pressure!
Paul Lamar
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