Main Page | Recent changes | View source | Page history

Printable version | Disclaimers | Privacy policy

Not logged in
Log in | Help
 

Measuring performance of watercooling components

From OCAU Wiki

When trying to understand the performance of a component, a very important point to remember is that the do not have a discrete value. Every component has one or more 'curves' ascossiated with it - is continuous data, usually something (such as pressure (dP), C/W, work (W) etc...) versus flow (dQ). This reinforces that when performance is concerned - flow is king (all things being equal)


Waterblocks

See the copper plate has a pin matrix which helps disperse heat, but also reduces flow.

There is generally only one graph associated with waterblocks, the flow versus C/W (or more commonly dT - much easier to measure as you do not have to quantify a heat source) graph. The curve shows the thermal transfer efficiency versus flow (known as a Q-C/W chart). This chart of often quoted when describing waterblock performance, it does not display the whole picture however. Take the Dangerden RBX for instance, an relitivly free flowing design, but not very 'efficient'. This would give it a 'high' curve on the Q-C/W graph - above the MCW6000 for instance. This graph does not take into account the relative restrictiveness of the pair though. It is easier to pump water through the rbx, this means that with a given pump, you will have a higher flowrate through the block, which gives a lower C/W value.

A more accurate graph is the Hydrolic Power (or work done on the block by the pump) versus C/W. This is a bit harder to understand, but provides a more accurate 'ranking' of a block.

Pumps

Pumps have one curve that is of major importance, the pressure versus flow curve (P-Q). This give the flow rate through a system for any backpressure produced by the loop. This curve of the LAING/DELPHI DDC from the LAING website shows power consumption versus flow too. Note that power consumption increases as flow increases. Also note that pumps do produce heat. This should be considered very carefully if you plan to fork out for a powerfull and expensive pump - it could provide worse system performance if your radiator is not up to scratch. Examination of the graph shows that it has a maximum flow of about 430L/H and max head of 4MH2O. If you can make your self a restriction curve for your system (an exceedingly difficult task to do properly), you can place it on the same graph, where the lines cross will give you your theoretical flowrate. P-Q curve for the Laing/Delpi DDC

Radiators

Radiator performance is exceedingly difficult to quantify accuratly.

Several things must be measured & quantified:

  • Change in temp from water to air (dT)
  • Flow of water
  • Flow of air

[Main Page]
OCAU News
OCAU Forums
PC Database

Main Page
Recent changes
Random page
All pages
Help

View source
Discuss this page
Page history
What links here
Related changes

Special pages