Subject: [FlyRotary]
Re: Heating the Fuel
Dave;
I didn’t read your e-mail
carefully enough, and had it in my head that you were suggesting that the fuel
in the tank would get to 190F. And maybe it could in a foam core fiberglass
tank like mine; but your course yours are metal and would get lots of cooling
from the air stream, so the temp probably wouldn’t go up much. And yes,
bubbles in the return line from the HE would re-condense in the tank; no biggie.
Your right, the problem is the low fuel
flow.
It sure would be nice to make use
of all that drag-free surface area of the wings.
Yeah, it would. How much surface area
could be made usable? A typical radiator with 16 fpi and 2 ½ in. thick has about
70 sq. ft. of core surface area per sq.ft of face area. So a 2 sq ft radiator
core probably has more area than you could get on the wings; and not addressing
the effectiveness of the areas.
Al
Evans coolant may just the stuff to
design a cooling system around. Simply route the heated coolant out to the
wing tips where it could passively drain back through shallow bays on
the lower surface of the wing and into a sump where an EWP could pump it back
to the engine pump. The bays in the wings would be very shallow to
minimize weight, they would be sealed but need not be pressurized. Evans
is the perfect stuff because it need not be pressurized, is very non-corrosive
and non-toxic.
Then there would be no need for a
radiator at all. Probably enough capacity there for a coolant/oil
heat exchanger and whala, zero cooling drag...
Tracy, is it too late
to make your RV-8 with zero cooling drag? :-)