Message-Id: <5.1.1.5.2.20031201061606.016bf948@popserve.lerc.nasa.gov>
Date: Mon, 01 Dec 2003 06:26:27 -0500
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
From: Joseph M Berki <Joseph.M.Berki@grc.nasa.gov>
Subject: Re: [FlyRotary] Re: radiator size
In-Reply-To: <list-2774052@logan.com>
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I am glad someone brought up cooling vs expected horsepower.  George was 
running three rads at one time and found that he had to pumb the rear 
heater (in the car) connection into the system.  His cooling problems went 
away.  Another successful rotary was Greg Riechters Cozy III.  He elected 
to go with jet power so we have not heard a lot about performance.  John 
Slade probably has numbers.  I believe Gregg was running over 488 cubic 
inches of cooling volume.  Right now I am leaning toward two of the large 
GM evaporator cores fed by a scoop under the belly that starts at 46 inches 
from the rad face and expands from the inlet opening to the rad face.  I 
thought K&W curve at the rad face would help.  The oil cooler will be in 
the strake closeout fed by another small scoop and will exhaust to the 
augmenter or overboard.  I wanted to use a single scoop to feed everything 
but i think it generates more air flow problems.

Joe Berki
Limo EZ


At 05:07 PM 11/26/2003 -0500, you (Marvin Kaye) wrote:
>Posted for Perry Mick <pjmick@viclink.com>:
>
>
>Ed, I think I have the record for minimal number of cubic inches of rad 
>cooling a rotary.
>
>The finned volume of my rad is only 12" x 14" x 1.5" (not including the 
>end tanks). This is only 252 cubic inches. I also have a 1 x 3 x 9 cooler 
>plumbed to the heater port for cabin heat, that is always on, only the 
>heated exit air is controlled into the cabin. So that is another 27 cubic 
>inches. Total is less than 300 cubic inches.
>
>It only works for me because I am producing relatively low power, 120 HP @ 
>5200 RPM in climb. And I have ducted-fan assisted airflow through the main 
>rad. Should I produce more power in the future this will probably not be 
>sufficient radiator.
>
>Trying to get more rad into a plane like the Long-EZ, just not sure how 
>you would do it. I think Joe Berki has removed some of the fuselage below 
>and behind the main landing gear, that should help.
>
>I use the NACA inlet to my rad also, but I expect it would not work so 
>well without the ducted fan or if your rads get thicker.
>
>I know Al Wick and have flown in his plane. With just Al, me and my 10 
>year old son on board, I think it took more runway for him to takeoff than 
>I normally do, and his climb-rate was less. So I believe he is not making 
>that much power, and his plane is not really a four-place airplane. Also, 
>I think the cooling requirements for a Subarooo just cannot be directly 
>compared to the rotary.
>
>I'm trying to think of a canard pusher flying at the moment under rotary 
>power, using a conventional prop, that Paul Conner could use as a guide. I 
>can only think of Ron Gowan's EZ that flew several years ago. Of course 
>there are several Cozys etc. under construction, so there is still some 
>trailblazing to do in this area. Fortunately for Paul, he can get a larger 
>rad in his plane than I can get in mine.
>
>--
>Perry Mick
>Custom Composite Props
>mick@bridgingworlds.com
>http://www.ductedfan.com
>
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