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I
don't clain to know anything about this topic, but a quick search found this.
These guys look like they're dealing with a bit more velocity and might be a
good starting point. There is a reference to the geometry they're using. You
might want to make them slightly smaller though :)
One thing that is meantioned is that, where possible you'll want
the air to expand first before going through the vanes because the energy loss
is proportional to the square of the velocity. Get the velocity down before
making a sharp turn ... where possible. In your case that would mean getting
them as far back from the inlet as practical.
Dave
<snip> .
Be aware that HVAC ducting is generally not dealing with
air flows that they have to slow down from 160 + MPH. While I do not
pretend to be HVAC knowledgeable - the environment and conditions are
different - that is not to say there may not be good ideas there - just a
different environment.
<snip>
Ed
----- Original Message -----
Sent: Monday, May 28, 2007 11:58
AM
Subject: [FlyRotary] Cooling
Recommendations
Rotary Group,
Thanks for the suggestions - questions etc.
Questions and--- maybe answers
Oil pan
clearance.
The oil pan is a flat bottom Renesis stock pan . In the
first picture sent 5/27 it is about level with the white motor mount tube
under the engine. At the front it is about 2 inches from the radiator
surface. At the back it is about 8 inches above the radiator.
The pan only covers some of the water rad. and none of the oil rad. I
get better cooling on the water side so I don't believe it is a
problem.
Duct shape.
My James cowl inlet ended about 3/4
inch inside the opening. I added foam and glass to make a smooth
transition to the bottom and sides of the cowl. Air entering near the
top of the inlet either turns up about 90 deg.within 2 inches of the
inlet to the air filter or goes straight back to the radiator. I don't
like this arrangement but don't know how much the turbulance contributes to
poor cooling. My first attempt to improve the top inlet flow made
cooling worse so I am looking at other areas now.
Water hose may be
restrictive.
The hoses in the first 5/27 picture are oil lines to the oil
cooler. An-10 to the cooler and AN-8 back to the engine.
The water
coolant hoses are AN-20 not shown because they are behind and on the other
side of the engine.
Turnning Vane construction.
I can easily
construct a support that bolts to the bottom of the cowl. This may be
able to be installed through the inlet without taking the bottom cowl off.
I have not found much information on flow turning vanes in either the
K&W Chapter 12 or Hoerner's Fluid -Dynamic Drag. Probably need to
look at HVAC duct design information.
Dennis
H.
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