I was always told to leave the stat in to slow down the flow of water, to allow
the heat exchange; removing it let the water whiz through before it had properly
cooled. Modern automotive myth? Or fact? Bill
Fisher, Michael L wrote:
> -----Original Message-----
> From: Fisher, Michael L
> Sent: Friday, May 31, 2002 5:45 PM
> To: 'jumpinjan'
> Subject: RE: Too Hot!!
>
> Not so,
>
> The radiator is a more efficient "cooler" than the engine is a "heater."
> This is because heat transfer from the radiator is via convection (it really
> should be called a convector not a radiator) and heat transfer in the engine
> is via conduction. Convection is typically dependent on (T_hot^5/4 -
> T_cool^5/4) and conduction is dependent on (T_hot - T_cool). So the radiator
> transfers heat to the ambient air more efficiently (read faster) than the
> combustion gases transfer heat to the coolant.
>
> This is really just a fluid transfer problem with a heat source and a heat
> sink. If you have MathCAD, I can forward you an analysis to show how this
> works. If you don't believe the physics, try it! Wait for a day where the
> ambient temp is about 85 F. Take out the thermostat and watch your car
> overheat. Put the thermostat back in and the car will not overheat. It
> works.
>
> -----Original Message-----
> From: jumpinjan [mailto:jservaites@woh.rr.com]
> Sent: Friday, May 31, 2002 8:37 PM
> To: Fisher, Michael L
> Cc: Rob Taylor; Alpine mailing list
> Subject: Re: Too Hot!!
>
> Mike,
> The thermostat regulates how much cool water flows through the
> engine.
> The radiator ALWAYS losses heat, so if the flow is not restricted the
> engine can't reach the operating temperture (160-180 degrees).
> Jan
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