Re: Cosworth V8 may be the most powerful in the pitlane?

Creamy Goodness wrote:
On Wed, 08 Mar 2006 12:41:58 +0000, Phil Newnham <pnewnham@xxxxxxxxx>
wrote:
Danielowski wrote:
Phil Newnham wrote:

This, I don't understand. Red Bull were cutting holes in the sides of
their sidepods too. If the engines produce less power (and surely they
must do) then they should require less cooling, so it should be easy to
step down to a V8 cooling solution from a V10. Unless they
underestimated severely, and the engine guys have managed to pull much
more power than expected from the V8.
I think it not a matter of power, but a matter of revs. Even if they
don't have as much power as with V10s, they should be near or over
20.000 rpms, with requires much more cooling than with V10s.
Why? We're running a bike engined 600cc racing car here, and it has a smaller radiator than, say, a 1l car does, despite revving to around 12,000 against the 1l car's 5500. It would have an even smaller radiator if it was geared to run as fast as the car does, because the cooling would be better with a higher airflow. The heat rejected from the engine through the radiator(s) is a function of the energy being released from the fuel, the efficiency of the engine (in terms of how much energy is converted to mechanical work at the flywheel, not miles per gallon or litres per kilometre), and how much heat energy is rejected through the exhaust system. Basically, the radiator's job is to get rid of whatever's left over:

Energy from fuel = Useful work + heat down exhaust system + heat through radiator

ignoring conductive cooling through the bodywork, which will be small, if the system is functioning correctly. Basically cooling requirement scales with power, not revs. Even at 20,000 rpms they still produce less power than the V10s - the laptimes they're pulling are due to improved aerodynamics and better tyres.

You've completely ignored friction, with your usual thoroughness.

Not one bit. Allow me to break it down for you:

Friction causes heat in the engine. Coolant absorbs heat from the engine. Coolant passes through radiator and is dissipated. Thus, the variable Phil labeled 'heat through radiator' is a function of heat from friction.

So, let 'heat from friction' = x and 'heat through the radiator' = y

y=f(x)

Thus, when including y in an equation, x is inherently included.

Thus:
"Energy from fuel = Useful work + heat down exhaust system + y"

is the exact same formula as:
"Energy from fuel = Useful work + heat down exhaust system + f(x)"

Cheers.
--
There's a fine line between not listening and not caring.
I like to think that I walk that line every day of my life.

-Forty
.

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