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pHaestus · 09-13-2003, 10:55 PM

Ok guys here's the deal. Knightelite is coming over to the house tomorrow to help me with doing a bit of testing. We settled upon an interesting topic brought up by BillA recently: REAL performance of pumps in a watercooling loop. So there are two ways to do that sort of testing. 1) Just hook a "typical loop" and a flowmeter to a bunch of different pumps and measure the resulting flow rates. 2) Add a valve and a pressure gauge as well. Measure pressure drop across the pump over a variety of flow rates, and construct a P-Q curve. You have to account for the head loss due to the flowmeter and valve so those will need to be measured as well. This is how I was planning to set things up for the second sort of testing (suggested by Bill in a previous thread):

http://phaestus.procooling.com/pumptest.jpg

This is where you guys come in. I have two questions regarding the impending flurry of test activity.

1) What constitutes a "typical" setup? Are more than one setup needed? One could, for example test with 3/8" tubing and 1/2" tubing to create a "high restriction" vs. "High flow" scenario. The parts must be identical for all tests of course. I was thinking that maybe a Black Ice Extreme or a Chevette heatercore (same as DD and DTek use) and a CPU waterblock would be the norm. Should I add a GPU block too? I have a few CPU blocks available but the Innovatek GPU block is the only one I have. I could say add 2 CPU blocks and a GPU block and a radiator with 3/8" tubing for a "worst case" type scenario too. Seem reasonable?

2) Are you guys going to find the P-Q curves useful? I would guess that the bulk of the pumps will fall right along the mfgr specs and so it will be an instance of lots of effort for something we already knew. There is some indication that the Eheim numbers might be a bit optimistic though, and several common pumps have P-Q curves created while submerged using a 1/2" NPT intake hole even though they are used inline with 1/2" barbs by our community. Does the final product (P-Q curves from my bench) justify the effort (this always takes a lot longer than you'd think)?

So anyway give me any comments on choice of parts for the "real world" testing and give me your interest level in the P-Q curve generation and when I wake up tomorrow I'll get started. I'll do the real world flow rate testing stuff first so I can go ahead and post that in any case.

09-13-2003, 10:55 PM	#1
pHaestus Big Player Making Big Money Join Date: Aug 2001 Location: irc.lostgeek.com #procooling.com Posts: 4,782	Pump testing Ok guys here's the deal. Knightelite is coming over to the house tomorrow to help me with doing a bit of testing. We settled upon an interesting topic brought up by BillA recently: REAL performance of pumps in a watercooling loop. So there are two ways to do that sort of testing. 1) Just hook a "typical loop" and a flowmeter to a bunch of different pumps and measure the resulting flow rates. 2) Add a valve and a pressure gauge as well. Measure pressure drop across the pump over a variety of flow rates, and construct a P-Q curve. You have to account for the head loss due to the flowmeter and valve so those will need to be measured as well. This is how I was planning to set things up for the second sort of testing (suggested by Bill in a previous thread): http://phaestus.procooling.com/pumptest.jpg This is where you guys come in. I have two questions regarding the impending flurry of test activity. 1) What constitutes a "typical" setup? Are more than one setup needed? One could, for example test with 3/8" tubing and 1/2" tubing to create a "high restriction" vs. "High flow" scenario. The parts must be identical for all tests of course. I was thinking that maybe a Black Ice Extreme or a Chevette heatercore (same as DD and DTek use) and a CPU waterblock would be the norm. Should I add a GPU block too? I have a few CPU blocks available but the Innovatek GPU block is the only one I have. I could say add 2 CPU blocks and a GPU block and a radiator with 3/8" tubing for a "worst case" type scenario too. Seem reasonable? 2) Are you guys going to find the P-Q curves useful? I would guess that the bulk of the pumps will fall right along the mfgr specs and so it will be an instance of lots of effort for something we already knew. There is some indication that the Eheim numbers might be a bit optimistic though, and several common pumps have P-Q curves created while submerged using a 1/2" NPT intake hole even though they are used inline with 1/2" barbs by our community. Does the final product (P-Q curves from my bench) justify the effort (this always takes a lot longer than you'd think)? So anyway give me any comments on choice of parts for the "real world" testing and give me your interest level in the P-Q curve generation and when I wake up tomorrow I'll get started. I'll do the real world flow rate testing stuff first so I can go ahead and post that in any case.