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gmat · 03-31-2001, 05:29 AM

I'm not exactly thermal engineer but engineer, yes. I think the flow rate has little relationship with temperature. Consider that a higher flow rate will give you a more uniform temperature all over the water circuit.
What counts is the thermal power of elements (negative or positive...). Say, if your WB pumps in 70W you'd better have a radiator which pumps out around 70W, or more.
One thing about low flow rate is, you gould quickly get a hot point in and after the WB. And you would not want water to boil inside it, would you ?
The higher the flow rate, the higher contact surface area you'll get. So you'll get more uniform temperatures around the circuit, and less 'hot spots'.
To make a long story short, consider that your WB/CPU interface temp has an inverse exponential relationship with flow rate. At low rates, a subtle variation in the flow will make big difference. At higher rates, it will make little difference.
With a single circuit (pump/wb/rad) and 10mm tubing you wont get much difference above 500l per hour... given you've got *real* 500 lph, which you'll never have. Mazes, turns and elevation all bring your flow rate down.
Thats it

I hope it was clear enough...

03-31-2001, 05:29 AM	#9
gmat Thermophile Join Date: Mar 2001 Location: France Posts: 1,221	I'm not exactly thermal engineer but engineer, yes. I think the flow rate has little relationship with temperature. Consider that a higher flow rate will give you a more uniform temperature all over the water circuit. What counts is the thermal power of elements (negative or positive...). Say, if your WB pumps in 70W you'd better have a radiator which pumps out around 70W, or more. One thing about low flow rate is, you gould quickly get a hot point in and after the WB. And you would not want water to boil inside it, would you ? The higher the flow rate, the higher contact surface area you'll get. So you'll get more uniform temperatures around the circuit, and less 'hot spots'. To make a long story short, consider that your WB/CPU interface temp has an inverse exponential relationship with flow rate. At low rates, a subtle variation in the flow will make big difference. At higher rates, it will make little difference. With a single circuit (pump/wb/rad) and 10mm tubing you wont get much difference above 500l per hour... given you've got real 500 lph, which you'll never have. Mazes, turns and elevation all bring your flow rate down. Thats it I hope it was clear enough...