Jerry Hey wrote:

Paul,  I have been trying to come to some finality on the
radiator
plenum.   I reversed  your process and started out with physical
model
of poster paper and plywood and then as I encountered problems,
tried
to work it out with cad.  Anyway,  here is what I have come up
with.
Please take it into consideration with the cowl designs.

     The cowl should slope back from under the spinner to a
point
5/8"
below the rear lower corner of the radiator header tank.  From
there
the louvers take over and it will flat and horizontal back to
the
firewall.  The flat bottom needs to be 14.5 inches wide to allow
room
for the louvers.

The photo was taken before I put the extension on the plenum to
get
it
out the front of the cowl. In the photo, the plywood represents
the
radiator and the duct tape is the header tanks.  The plenum
opening
is
48 sq in which expands to 71.5 sq. in.  before it enters the
wedge
portion.   Jerry

     Don't need to do that. Keep a constant AREA duct up to the
start
of the core.

     Paul Lamar

Jerry,
Have you bought a spinner yet? I'm planning on a 16" spinner
also,
maybe from a mustang II, and was wondering about the price. Your
radiator has the same dimensions and looks like your inlet duct
is
similar to what I'm planning.

Brian Trubee

No,  I have not bought the spinner yet.  I think the Mustang 2
spinner
will be quite expensive.  If we could get a few guys together, we
might
be able to get Brian Alley to build us some CF spinners.  His work
is
beautiful.    I have not talked to him about this and have no idea
if
he would do it or the price.   Jerry

I got some bad news for you Jerry. No way is that stock cowl and 12
inch spinner
going to work.


Paul Lamar

Interesting.   According to my mock up of which I have sent a number
of pictures, including one today showing clearance with the 12 inch
spinner,  I have plenty of clearance on top for the runners.  The cowl
should be  about 34 inches wide at the S beam which is 31 inches
overall.  What is the height at the firewall of the cowl  you have
drawn? What is its width 35 inches in front of the firewall?   Jerry

You are fooling yourself Jerry as that line does not go all the way
across
the top of the cowl. You got to do this stuff in 3D. I'll send a
drawing
with dimensions.

Paul Lamar

Here are the real numbers on my cowl width at the end of the S Beam.
As  you can see,  I have plenty of room.    Measured by Brian Alley
today.   Jerry

"Jerry, I measured the mold and it is 34" so I'd say
the cowl with coremat is 33 1/2" at 24" forward of the
firewall and 6" below the prop centerline. Call me in
the shop tommorrow. I'll be here all day!!!

Send me a sketch of what he is talking about. Is this the width
of the cowl 24 inches in front of the firewall six inches below
the thrust line? Is so what does that have to do with the top
surface of the cowl? It is the top surface of the  stock Tailwind 
cowl being as low as it is that causes problems with the wrap over 
intake manifold. Get a quote from him on a new cowl design.

Paul Lamar
 
The Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2004 All world wide rights reserved.