Another interesting tid bit was the the fact that the S.6B's RR engine
was rejecting 40,000 BTU each minute by the surface radiators
covering almost every square inch of surface on wings and floats.
40,000 BTU's/min  is 703,333 Watts! Or 1,280 HP worth of waste
heat. In the earlier, S.4 design, the conventional cooling radiators
mounted in the wings were responsible for 38% of the total drag.

Hi all:

        I thought about a surface radiator for the Cozy oil cooler
but haven't pursued it very hard because of:

        1) Maintenance - Porsche tried it in the 50s-60s on their racing cars
        and gave up due to leaks.

        2) Weight - The surface would need to be alumimum plus the piping,
        etc. I thought about using that carbon conductive foam but corrosion...

        3) Temp - I'd have to insulate the cooling surface from surrounding
        structure - not a biggie, but still weight.

        Of course, NO drag is the driver here! If someone has better/different
ideas/fixes for these problems, please let me know.

Regards,
James

The no drag issue has been disputed by numerous aero types, but I do not
think that it is a closed issue. I am convinced that while there are areas
where heat input would be drag, I am equally sure that there are areas
where heat addition could add thrust (ie external burning ram jets)
Vance

I have been thinking about this for the past few years off and on.
IMHO the reasons it did not work very well in the P51 was because
of the modest compression ratio of the cooling duct. Not much you can
do working with the dynamic pressure available to us. This is true
for all forms of internal combustion engines including turbines.

On the other hand at supersonic velocities much higher compression 
ratios are available because of the much higher dynamic pressure.

I think a much more fruitful sub sonic approach would be to recover
some of that 50% waste heat in the exhaust using a blow down turbine.

Paul Lamar
 
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