On 11 Nov 2007 at 21:24, DLylis@aol.com wrote:
> I ain't no scientist, but when a temperature gradient is set
> up does the coolant not do it's level best to become all the
> same temperature?
Well, yes, but it's a question of how fast. And what other things
are going on.
The only physical connections between coolant in the radiator and the
coolant in the block are the narrow diameter radiator hoses. When
the engine is running the heat transfer due to water convection is
very much greater than the heat flow through the water itself, which
is how it keeps the block cool at all. Meanwhile, air convection
happens within the engine compartment. This carries heat away from
the block so that eventually it will cool down by itself. Depending
on various engineering values (i.e. specific features of each car)
rather than science per se, either of these phenomena could be
faster. Certainly keeping the fan on could help air flow around the
block if the air can't convect by itself. But neither of these
phenomena is fast compared to the water flow when the engine is
running. Yes, keeping the fan on would cool things down a little
faster, but only just a little and nothing under a Triumph bonnet
would benefit from it.
--
Jim Muller
jimmuller@rcn.com
'80 Spitfire, '70 GT6+
--
Version: 7.5.503 / Virus Database: 269.15.28/1123 - Release Date: 11/10/2007
3:47 PM
_______________________________________________
Support Team.Net http://www.team.net/donate.html
This list supported in part by the Vintage Triumph Register
http://www.vtr.org
http://www.team.net/donate.html
Triumphs@autox.team.net
http://autox.team.net/mailman/listinfo/triumphs
|