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pHaestus · 04-30-2002, 12:47 PM

A person's individual setup can't change the fundamentals of heat transfer. Look at this:

http://www.efunda.com/formulae/heat_...iew_forced.cfm

Note the delta T term (block surface temperature vs. water temperature in our case). There is no way to increase this term (and enhance heat transfer rates) other than to increase flow through the block. What about that h term though (the convection heat-transfer coefficient)? This is related (among other things) to the thickness of the boundary layer of water on the surface of the block. Here is a nice overview:

http://chemeng1.kat.lth.se/staff/ulf_b/b3_heat.htm

Increased water velocity (and therefore turbulence) will decrease (but not eliminate) the boundary layer of water at the surface. This improves heat transfer markedly compared to laminar flow through a larger boundary.

For a given block, performance will always increase with flow rates. However, in a complete cooling system the radiator and pump will not and so there exists a "sweet spot" where flow rate is optimized for the components that are used. I said this in the beginning btw.

04-30-2002, 12:47 PM	#18
pHaestus Big Player Making Big Money Join Date: Aug 2001 Location: irc.lostgeek.com #procooling.com Posts: 4,782	A person's individual setup can't change the fundamentals of heat transfer. Look at this: http://www.efunda.com/formulae/heat_...iew_forced.cfm Note the delta T term (block surface temperature vs. water temperature in our case). There is no way to increase this term (and enhance heat transfer rates) other than to increase flow through the block. What about that h term though (the convection heat-transfer coefficient)? This is related (among other things) to the thickness of the boundary layer of water on the surface of the block. Here is a nice overview: http://chemeng1.kat.lth.se/staff/ulf_b/b3_heat.htm Increased water velocity (and therefore turbulence) will decrease (but not eliminate) the boundary layer of water at the surface. This improves heat transfer markedly compared to laminar flow through a larger boundary. For a given block, performance will always increase with flow rates. However, in a complete cooling system the radiator and pump will not and so there exists a "sweet spot" where flow rate is optimized for the components that are used. I said this in the beginning btw.