Mailing List flyrotary@lancaironline.net Message #35748
From: John Downing <downing.j@sbcglobal.net>
Subject: Re: [FlyRotary] Re: cowl openings for water radiators
Date: Mon, 26 Feb 2007 20:53:52 -0500
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Ed, is there some particular reason that you necked the inlet down small, then enlarged it again.  Thankyou for the pictures.  JohnD
----- Original Message -----
Sent: Monday, February 26, 2007 3:39 PM
Subject: [FlyRotary] Re: cowl openings for water radiators

John, don't know if these photos will help.  But, like you I only have between 3 and 6" of duct distance on the radiators.  You should do Ok with 20 sq inch on each opening with a good diffuser/duct.  Attached are some photos of my current ducts.  The openings are 18 sq inches each.  I have had one opening down to as little as 10 square inches - but that was a bit marginal - so opened it back up.  I have a generous exit area for the hot air including a larger 4" x 12" bottom opening as well as louvers on each side of the cowl.  So you mileage could vary - but Tracy has essentially the same size opening as well as several others.
 
Ed
----- Original Message -----
Sent: Monday, February 26, 2007 12:12 PM
Subject: [FlyRotary] cowl openings for water radiators

What size openings do I need for the water radiators?   The Wittman Tailwind cowl I have has postal slots of 3' x 7 3/4" , which is   approx. 22 1/4 sq in. on each side.  Sam James for the 160 Lycoming is using 4 3/4' round holes which are 17.6 sq. inches on each side.  My radiators are quite close to the opening and I plan on making the diffusers trumpet shaped, will the openings be large enough if I can stay over 20 sq. inches on each side with a decent trumpet shape.  JohnD       hushpowere II on order - hope to start in 2 weeks if weather cooperates.


--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/


--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net/lists/flyrotary/
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster