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Extending the logic- when flow is zero, cooling is infinite. :o)
(?)
Jack Ford
----- Original Message -----
From: "Bulent Aliev" <atlasyts@bellsouth.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Monday, March 21, 2005 8:10 AM
Subject: [FlyRotary] Re: BMW and EWP
> Jim, by the same reasoning, when you are hot and sweaty in front of your
fan
> at home: The slower the fan turns, the colder you get since the air has
more
> time to pick up heat from your body? :)
> Buly
>
> >
> > I had looked at it as:
> > High Flow - engine can't heat the water as much as it would if the flow
> > were slower and there was more time to heat the water, resulting in less
> > temp rise in water across engine and more uniform temps in the block.
> > Water emerges from block not much hotter than it went in. Water doesn't
> > stay in the radiator long enough to be exposed to air flow long enough
> > to be cooled very much. Good news: it doesn't *have* to be cooled much
> > - it's not all that hot.
> > Low Flow - coolant spends more time in engine and gets hotter. Greater
> > dT across engine block, coolant hotter exiting engine and entering
> > radiator. Radiator has to draw more heat out of the coolant to get it
> > back to acceptable block entry temp, but has more time to do it on
> > account of lower flow.
> > What I hadn't seen, is how apparently wide a range of flows would
> > produce acceptable results. I suppose a better radiator (more flue
> > area, better air flow, etc. - better cooling per in^3) would reduce the
> > volume requirement. Lower limit on flow would seem to be that flow at
> > which the temperature gradient across the engine becomes unacceptable.
> > Thanks for the details ... Jim S.
>
>
>
> >> Homepage: http://www.flyrotary.com/
> >> Archive: http://lancaironline.net/lists/flyrotary/List.html
>
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