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Cathar · 09-19-2005, 08:15 PM

Hey, it's all good. Like all science once you dig down deep enough, it trascends the simplistic secondary-school-room level and becomes pseudo-philosophical.

What you're calling the thermal boundary layer, more commonly referred to as simply the "boundary layer", is a basic given in the convectional thermodynamics, being the boundary between static conduction of the liquid-metal interface and convective motion. Could argue for days over the strict definition of what's going on at this level with respect to potentially mobile liquid molecules interaction with the metal surface. Some trains of thought suggest that the molecules that touch don't move at all, while others suggest they do move, albeit very slowly, but can be effectively treated as if they were static for purposes of considering the thermal boundary transfer layer as being primarily, or solely, conductive.

This level of theory doesn't interest me too much though. I'll leave that to the university lecturers. I'm more interested in assessing gains and understanding the theory to a necessary point to predict whether some design change is going to have a desirable impact. I do my best to understand just as much as I need to in order to forge ahead, which is probably why I ended up dropping advanced physics by third year university because it got too hand-wavingly theoretical. I do admire the guys though who spend their lives breaking it all down and analysing it to the nth degree and formulating the theories for it, but I learned long ago that my interests were more founded in understanding the theory just deep enough to allow me to experiment to push things along.

What I think now may be beneficial is looking at some ways to further disrupt the boundary layer. There's been research done on pulsating flows which seem to suggest that this can work well, but the implementation of such within a waterblock is the tricky bit, not to mention the potential for additional stresses on the pump and other components.

Perhaps a spinning disc with a scimitar slit pattern located above the jet intakes providing a constant pressure drop resistance upstream to the pump, but giving localised pulsating flow input into the jets would be a way to implement such?

09-19-2005, 08:15 PM	#52
Cathar Thermophile Join Date: Sep 2002 Location: Melbourne, Australia Posts: 2,538	Hey, it's all good. Like all science once you dig down deep enough, it trascends the simplistic secondary-school-room level and becomes pseudo-philosophical. What you're calling the thermal boundary layer, more commonly referred to as simply the "boundary layer", is a basic given in the convectional thermodynamics, being the boundary between static conduction of the liquid-metal interface and convective motion. Could argue for days over the strict definition of what's going on at this level with respect to potentially mobile liquid molecules interaction with the metal surface. Some trains of thought suggest that the molecules that touch don't move at all, while others suggest they do move, albeit very slowly, but can be effectively treated as if they were static for purposes of considering the thermal boundary transfer layer as being primarily, or solely, conductive. This level of theory doesn't interest me too much though. I'll leave that to the university lecturers. I'm more interested in assessing gains and understanding the theory to a necessary point to predict whether some design change is going to have a desirable impact. I do my best to understand just as much as I need to in order to forge ahead, which is probably why I ended up dropping advanced physics by third year university because it got too hand-wavingly theoretical. I do admire the guys though who spend their lives breaking it all down and analysing it to the nth degree and formulating the theories for it, but I learned long ago that my interests were more founded in understanding the theory just deep enough to allow me to experiment to push things along. What I think now may be beneficial is looking at some ways to further disrupt the boundary layer. There's been research done on pulsating flows which seem to suggest that this can work well, but the implementation of such within a waterblock is the tricky bit, not to mention the potential for additional stresses on the pump and other components. Perhaps a spinning disc with a scimitar slit pattern located above the jet intakes providing a constant pressure drop resistance upstream to the pump, but giving localised pulsating flow input into the jets would be a way to implement such?