Brian,
There you go mate, your doing everything Paul's suggested and now he
changed
his mind - completely !!
George (down under)

I am never satisfied with the status quo :)

BTW What Brian is proposing is fundamentally
the same as the new idea except the rad can be even larger if

necessary.

A rad that large will probably be under the engine and will probably

dump

the air straight down out of the bottom of the cowl. That is the only

way

it is going to work well.

I find it kind of strange people are jumping all over me for the new

idea

when they accept this arrangement without question. IMHO kind of

strange

psychology.

A little like a shark feeding frenzy :)

Paul Lamar

Paul,
 Forgive me mate I'm a bit of a joker - I like a laugh now and again.
I understand your a more serious person!

What I was alluding to is -we that are ignorant of all that is involved

in

cooling (I speak for myself here) have just, after many years, just got

used

to a logical concept and you just turned it on it's head.

Not true it is only a minor modification and improvement.

My understanding was that to reduce drag and eliminate the boundary

layer a

smaller P51 type opening was necessary - we needed to slow down the air,
compress it, turn it 70 (approx) degrees (the slow turbulent air

absorbed

the heat better) and shove it out the back with louvers controlling the
process.

The opening is the same size. The diffuser is the wedge over the rad.

Instead of taking too much air in and controlling the flow with
louvers we can open and close the inlet by raising and lowering the
front of the rad. You can still use lovers if you wish. There is
nothing about this idea that prevents that.

Now were going full opening (however the slope of the radiator would

reduce

the frontal area to that similar to a scoop opening) ie 30%, and were

going

for a straight through radiator with the associated speed of air and
ignoring the boundary layer.

We don't have to ignore the boundary layer. If you want to provide
a boundary layer bypass all you need do is provide a flat top plate
for the rad and space the whole works down several inches below
the fuselage.

Hey mate if it works as well, I will be the first to say

congratulations,

your a genius. However my poor brain can't move from one concept to

another

that fast without some confusion. I guessing from the discussions - some
other builders may feel the same way.

No criticism of the concept intended.

George (down under)

I did not think of this idea. Several airplanes are flying with it
successfully. I merely noticed it at OSH and was amazed at it's simplicity
elegance and beauty. Peter Cowan on here has it on his Rans S7 float

plane.

Paul Lamar

Just had another thought. I think I will go this route if I can fit it into
the cowl. Call it a hybrid.

Mount the wedge duct onto the top of the rad. Attach louvers or a screen to
the bottom of the rad. (or leave it open)
Hinge the back of the rad so it can be lowered into the airflow under the
airframe during taxi, take off, and climeout.
Retract it back into the bottom of the cowl, to match a small internal duct
from under the prop, during cruise.
The top of the wedge seals the cowl bottom when open and the bottom of the
rad is flush with the cowl during cruise.

Slam away!

Ron Freier
Vision 2+2 13B Turbo (someday!)

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