Subject: Simple cheap and no work cooling system.
From: ACRE
Date: 9/4/2003, 10:51 PM


What would this look like in a Canard pusher installed?

Butt UGLY
...Chrissi


You would not even notice it with nicely styled side plates.

You will not see it standing along side from any angle. You will only
see it if you lie down on the ground.

What do I have to do draw you a picture? :)


Paul Lamar

IMHO - this thing is drag city. For any opening area you will take a full
head loss.
For example if you have an opening 0f two inches height for your 36 inch
width
you will add a full half square feet of flat plate drag. At 200 mph that is
rougly
50 pounds  or 27 horsepower. You are bringing in this air at full ram
velocity and
dumping it out sideways with no rearward  velocity component - NO recovery!
Your "free lunch" just emptied your wallet - and no matter what you say
"the air thinks that it is UGLY" - Vance

It depends on the rad porosity Vance. 
Modern rads are thin so the air goes through them easier. I would be  
very surprised if more than about 50% of dynamic pressure was developed 
across the opening.

Lets say it is a half square foot and a CD of .5 that is that is about
25 pounds of drag at 200 MPH or 263 feet per second or 6,600 pound feet 
per second or 13 HP loss.

The external drag of a perfect P51 scoop with a perfect K&M diffuser is also 
finite with perhaps 80% of dynamic pressure over an opening of 25% to 35% of
the rad frontal area dimensions of 20 by 16 or 2.2 square feet. 30% of that 
is .66 square feet so on that basis a perfect P51 scoop is  still 
about 13 pounds of drag with a Cd of .25 or six HP. 

So maybe it is a six HP drag penalty. Worth it if it cools.

Bottom line is we don't have room for a perfect K&M diffuser
and a P51 scoop.
 
It is also  unlikely to be 36 inches wide more like 20 inches.

Since the water tubes are aligned with the longitudinal axis it is 
possible we can find a core manufacturer to build one with the fins between
the tubes orientated at an acute angle to reduce the drag.
As per Chrissi's suggestion.

Paul Lamar
 
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