Aftercooler Gains

[Greg Hermann]

At 8:53 PM 4/17/01, David Gregory wrote:
>Just to interject and comment on the idea of using a vapor-compression
>system to cool the intake charge.  If this unit is intended for use on a
>street car, I don't think it would be necessary to size the AC system based
>upon max power output.
>I've thought about this before, and i think that the way to go would be to
>use a water-air intercooler and then use the AC system to cool the water
>that is circulated.

Nice idea, and surely a bit easier to control. You are going to give away a
bit of cycle efficiency--because of the lower suction temp that you would
have to have because of the extra heat exchanger between the refrigerant
and the coolant, but if it were done with a plate type evaporator, this
would only amount to 4 or 5 degrees F.

With a more conventional shell and tube evaporator, you would be looking at
more like a 10 or 12 degree F penalty.

lso take longer to return to acceptable
>level.
>I think that this idea could work with an automotive style AC compressor on
>a street or even a drag car... just not on a road race car where you would
>need to make full power continuously for a considerable amount of time.

All correct. Pulling a trailer up a mountain grade is probably the worst
case scenario---
>
>Now, if you wanted to get really crazy and spend lots of money, you could
>use thermoelectric devices :)

Nice thought, escept for the fact that thermoelectric devices are about 3%
efficient!

Greg
>
>David Gregory


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