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[FlyRotary] Re: Performance coatings- bearing damage?
Dave,
In current return systems, returning the fuel from
the fuel rail alone to a header tank is a NO! NO!
The residual heat in a small fuel tank isn't
sufficient to cool the fuel before it goes back into the fuel rail - it causes
vapour lock.
All return fuel, I have been told , must return to
the much larger tanks to dissipate the heat
The Wankel Rotary which has fuel cooling the
rotors is suspect in this regard. I have no facts on this, only what has been
discussed on other sites.
Given this information I believe you may have a
considerable problem with heat.
George ( down under)
Sent: Monday, February 07, 2005 3:46
PM
Subject: [FlyRotary] Heating the
Fuel
In
anticipation of the new turbo, I am considering ways to improve coolant
cooling. Besides the obvious more air, more ducting, more radiator; I
have been again toying with the idea of a heat exchanger. This time
coolant to fuel. The plan would be to use a typical oil/water exchanger
but use fuel instead of oil. I would use the fuel on the way back to the
tank, and the coolant after it has already been cooled by the radiator.
The fuel would then go back to the nice metal tank of the
RV.
I am
looking for input on the implications of heating the fuel. I expect it
would reach max temps of about 190 (usually a little cooler) but
quickly cool once in the tank. Can the fuel tolerate that temp without
vaporizing? It will probably expand in the tank but I don't expect that
will occur faster than it is used up. I have no guess as to what temp
will become steady state for the fuel pumped out of the tank. My guess
is that it will not be much warmer than normal, but a slight increase in temp
may help with vaporization.
The
last question is how much will it cool the coolant. My hope is about 10
deg but I doubt it will be quite that much. I know others have
considered using the fuel to cool (Tracy) and I would appreciate your
thoughts.
Dave
Leonard
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