|
I am having problems getting my oil temperatures below 200
degrees with outside temperatures at or around the 32degree level. Most of
the time I am running at 220 to 230 degrees.
I have a NACA duct on the right hand side of the cowl
four inches below the split line and approximately 2/3rds of the the way back
from the front of the cowl. This duct connects with a 3inch diameter SCAT
hose. This hose leads back from the duct and goes through a long radius
90degree bend and enters the cooler plenum chamber from the top. The
cooler is mounted on the right hand side of the fire wall and the air
flow is down through the cooler. The air then exits from the cooler into
the lower portion of the cowling and out to the exterior of the plane.
There is no duct or hose on the discharge side. The cooler is a 9 row
unit.
The NACA duct is one I bought from Butler and is normally used
on race cars. Is there an optimum length for the opening on the cowl side
to ensure the air flow enters the duct in sufficient quantity?
Looking at the cowling from the front of the plane the opening
is invisible as the cowling which is non standard is slightly wider at the front
than the firewall so it is a slow taper to the firewall. There may be a
dead spot there.
I did put a deflector on the lip of the duct, would this help
to get air into the duct and would bending it further out into the slip stream
improve the air flow?
I intend to verify the accuracy of the gauge in boiling
water.
Does anyone have any good ideas?
Happy New Year to all
Ian Crowe.
|