I suspected it might be the opposite of our tractor aircraft. Bobby
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Charlie England
Sent: Monday, May 14, 2012 12:33 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Possible cooling solution?
I'm not sure I'd get too excited about a top exit. Yes, it will cool down faster after shutdown, but that's not the real goal.
There's a lot of 'pressure recovery' (pressure is going *up*) when you get to the rear of something that resembles an airfoil. Thorp T-18's have the cabin cooling inlet at the base of the rear of the sliding canopy, & they will part your hair in the back.
I managed to find this image of Pushy Galore (2nd fastest Reno F-1 racer at the time). Note the rather hard to see cooling inlet, about 1/2 chord at the wing root.
Also, here's a web page by an EZE builder who did his homework.
http://x-jets.com/downdraft_cooling.html
Charlie
On 05/14/2012 11:31 AM, Lehanover@aol.com wrote:
Since you are moving your inlet to the bottom have you considered a top exit? Is the top cowl area close to the prop in low pressure? I'm sure your turbo provides plenty of extra heat during ground operations.
Bobby
Plus you get faster cool-down from chimney effect. Air intakes in high pressure areas work great. In low pressure areas, not at all, or flow backwards. Surface mounted intakes require the flow be attached ahead of the intake to function. So, a few vortex generators often do the trick. The scoop style operating in undisturbed air will work perfectly.