Paul

I have attached 2 drawings in auto cad not very good but I think your smart
enough to
figure it out what I have is a Long Ez with cessna 210 retracts on it you
can see it
at www.myairplane.com click on construction log and then Tonyslongez anyway
which of
these 2 drawings would work best for my application and I was wondering if
you had
time to draw it 3-d so I can start modeling the intake

Thanks Tony

P.S. I hope to see you at oshkosh.

Hi Tony. for 2D drawings hit shift Print Screen on your keyboard.
Load Windows Paint and press Paste.
Save As jpg. Your 2D dwg will now be in jpg form which
you can attach to your email messages. Saves a lot of work for me :)

Interesting idea you got there. Rule of thumb it takes about
600 cubic inches of rad volume to cool a rotary so a thick vertical
rad 15 inches wide and 10 inches high would have to be about 4 inches thick.
The first 1/3 of the rad does 3/4 of the cooling and the second
half does 1/4 of the cooling. Another old rule of thumb.
Not too good at our takeoff and climb speed ranges of around
80 120 MPH as it takes a lot of dynamic pressure to force air
through a thick rad. It will work but you might not be happy
on a hot day.

Modern highly efficient heat exchangers tend towards large frontal area with
minimal thickness. This late model Dodge PU rad is a good example. So laying
it down at an angle seems to be the best solution. I modified your drawing
to show the dimensions and a slightly better configuration.

Paul Lamar

Seeing the transmission cooling lines on the picture of the truck radiatior
made me wonder why we could not run the oil thru this radiator as well.  Is
there too much oil pressure?  If so what could we do to reduce the pressure
as it comes into the radiator?  Even if we needed an additional small oil
cooler, this could help???

Bill Bradburry


Been there done that Bill. Here is an excerpt from my airtilce
on the web side names How to Cool youe Wankel.
http://www.rotaryeng.net/cooling.html

"Don't be tempted to use an oil to water heat exchanger for oil cooling.
Several builders have tried this and failed miserably.  A fundamental factor
in the process of heat transfer is the difference in the temperature of the
two mediums. The rate of heat transfer in any heat exchanger is proportional
to this temperature difference. In an OIL TO WATER heat exchanger this
difference could be as little as 10 degrees Fahrenheit. Water 220 oil 230
degrees F.  In an OIL TO AIR heat exchanger this difference is usually about
100 degrees F or more. An OIL TO WATER heat exchanger adds to the water
cooling problem and reduces the margins of safety between normal operation
and unstable operation. (Bulk coolant boiling). An OIL TO AIR heat exchanger
oil cooling system on the other hand is a stable system as oil boils at a
temperature well above normal oil operating temperatures. (Nothing worse in
the middle ages than being boiled in oil.) It is also a parallel independent
cooling system and will continue to function when the liquid [water] cooling system
fails giving additional time to get the aircraft on the ground. This is not
the case when an oil to water heat exchanger is used. In that case all your
eggs are in one basket."


Paul Lamar