[SOLVED] Is there ANY point to Push/Pull fans on a water cooling radiator?

Imacflier

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Jan 19, 2014
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Hi, All,

In the absence of flow resistance (e.g. a radiator) the most air a fan will pass in push/pull is the SAME as what it would pass if operating alone. When there IS a resistance (a radiator), a push pull set up can do no more than approach the flow where there is no resistance. Therefore, unless there is significant resistance to flow in a radiator, there is NO POINT in push/pull!

Am I missing something here? My jackleg (i.e. non-quantitative) airflow testing through 200mm radiators show effectively no drag at the velocities our fans operate at.....so do I save the money and just use one fan per radiator?

Speak up! Please advise!
I promise not to make fun of your answers and advice (well except where it is arrant nonsense, of course)!

Prompt responses get bonus points!

Larry
 

Imacflier

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Jan 19, 2014
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If push/pull were really beneficial, we'd all be doing it.

I've not seen ANY performance tests where it makes a real difference over just fans on one side.


Well, we now have some quantitative data: since I fly radio controlled aircraft, I have an optical tach in my toolbox. I dug it out, measured fan rpm both as a single fan blowing through an 85mm thick radiator and repeated with push/pull fans. There was effectively NO DIFFERENCE in the rpm of the same fan between the two configurations.....so I just saved a bunch of space and $ (Noctua 200mm fans ain't cheap!)

Thanks for the response, and

Very Warm Regards,

Larry
 
Well, we now have some quantitative data: since I fly radio controlled aircraft, I have an optical tach in my toolbox. I dug it out, measured fan rpm both as a single fan blowing through an 85mm thick radiator and repeated with push/pull fans. There was effectively NO DIFFERENCE in the rpm of the same fan between the two configurations.....so I just saved a bunch of space and $ (Noctua 200mm fans ain't cheap!)

Thanks for the response, and

Very Warm Regards,

Larry
I'm glad you went and verified the assertion.

There's way too many people who believe some assertion they read on the internet without verifying the assertion is true and/or in what cases the assertion is true.
 
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