Flow Rate and Temperature
Does anyone know of any benchmarks or real numbers showing flow rate in a water cooling system compared with temperature?
I found a great thread (Flow Rate Impact in Water Cooling) but they didn't show any real numbers.
I recently put my first WC system together and I want to better understand how I can manipulate & control my temperatures.
I used the MCP655 w/ Speed Controller with the hope that I could control the noise and temperatures, just as I can with my speed controller on my fans.
pump specs:
Maximum head - 10 ft (3.1 m)
Maximum discharge - ~ 317 GPH (1200 LPH) == maximum setting
They have a nice chart on that page that shows flow rates at the different settings.
The flow rate range is from ~350 LPH to 1200 LPH for the lowest and highest setting.
http://2xod.com/articles/WC/MCP655-800X500.PNG
I would guess that going from the lowest setting to the highest setting would have a fairly significant impact on cooling performance, but I do not see any change when I actually tested this theory.
Here is my testing method: (quick and dirty)
1) Pump is at lowest flow rate (~350 LPH)
2) Run prime95 to increase cpu usage to 100%. this should give me the highest possible temps in the system.
Wait 5 minutes for system to reach highest temp.
3) Wait another 5 minutes to see stable temps at lowest flow rate. Record avg temp (26.5 C)
4) Change pump to highest speed setting (1200 LPH) wait 5 minutes for temperatures to stabilize. Record avg temp (26.5 C)
Here you can see this happen on speedfan:
http://2xod.com/articles/WC/flow rate and temps.GIF
Am I not waiting long enough for the temperatures to change? I imagine the water cooling system may need a little longer to get full equilibrium with the heat exchange between the cpu and rad, but shouldn't I see at least some kind of change between the lowest and highest flow rate??
I will be repeating this test overnight for the next 2 nights. The first night I will log the temperatures all night at the lowest flow, and the second night with the highest flow. The other motherboard temperature sensors will give a good idea of the ambient temperature as a reference point between the nights. I hypothesize that the results will be the same, but how can it be explained??