X-Mozilla-Keys:                                                                                 
Russell Kent wrote:

Byron Brandon Ward wrote:

Is it possible to use a turbocharger to provide all of your cooling air?
If so couldn't you make a cooling system much more efficient by
transfering the heat to high pressure air? Is their a quick and dirty
formula to figure out the radiator area needed based on the amount of heat
you are rejecting and the specific heat of air, etc?

Paul Lamar responded:

The problem with a turbo charger is it is designed to compress
the air and that adds a bunch of heat. What you want is a high
volume low pressure blower for cooling air. Using the waste exhaust
energy to drive the blower is a very good idea so you would need a
gear reduction on the exhaust turbine.

Perhaps it is a good idea, and perhaps not.  I tend to take the stance that if
it were such a good idea we would have seen automobiles with it.

How many aircooled automobiles have you seen recently Russell?
The FW 190 BMW aircooled radial engine had a gear driven cooling fan.

I have an alternate implementation.  Let the exhaust turbine spin a
generator/alternator.  No gear reduction needed.  Then add a thermostatically
controlled fan to the radiator.  More throttle = more generated electricity =
more power for the fan to deal with the excess heat.

Of course this idea also fails the above "sanity test."  :-)

Russell Kent

Now that I have to see. An alternator that will live at 50,000 RPM :-)
 
Paul Lamar
 
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