oil cooler air

[JDanno]

Has anybody tried to cool their oil by installing a NACA duct and getting air from there? I'm standing here looking at a huge hole near the back of the #6 cylinder and wondering how nice it would be if all that air was blowing down thru the cylinders cooling them. I don't want to start hacking holes in the cowl until I find out if anybody has had success doing so. Thanks!

 

[Toobuilder]

Someone will shortly jump in with all kinds of engineering data, but the end result is pretty simple: NACA ducts don't provide any appreciable ram effect to create a useful pressure delta across a heat exchanger. They are low drag ductwork, not scoops. Very effective in some applications, but not this one.

 

[JDanno]

It sure blasts a lot of air out of the air vents along the sides. But there is no back pressure involved there like it is thru fins on a radiator. Guess that's the difference.
I know on Navions the oil cooler is supplied via a NACA duct on one side. Something I've observed but don't know how well they work.

 

[grubbat]

Not the best

The NACA scoops are not the best solution, but it has been used on certain Maule models and may work ok if you don't have any other options. A large NACA scoop is used on the mooney where most folks would prefer to have a pressure setup but i guess Mooney figured out how to make it work. A NACA scoop for a 4" round duct would be a rather large scoop.

 

[BillL]

Not a NACA, but it is a scoop

Alan Judy's RV6 - it does not open very far, but he said it cools like a monster.