Which Noctua 140mm case fan for airflow?

I am looking to get some noctua 140mm fans for my Corsair 750D but I am not sure which one is optimized for airflow. I do not have any restrictions blocking airflow. Here are the fans.
NF-A14 FLX
NF-A14 PWM
NF-A14 ULN
NF-A15 PWM
 


The problem is that I am not sure if that fan is better for radiators and heatsinks (static pressure) or for case airflow.
 

mbarbantini

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Dec 4, 2013
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Oh now I understand;
Noctua NF fans are focused on case airflow so yeah you could get any of those but the PWM provides the best efficency :)

Sorry for not getting it, I thought you were asking me which one provided the best airflow performance :/

Hope I answered your question now!

Have fun upgrading (if you are)!
 
My problem is that everywhere I go, everyone only taks about these fans for static pressure (heatsinks and radiators). I need to find a source that tells me that the fan would be for airflow and not static pressure. The NF from what I know does not mean that it is for airflow. They all say NF, even their 120mm fans made for static pressure. I just cant find anywhere in the world where someone mentions 140mm Noctua fan or airflow and NOT static pressure.
 

mbarbantini

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Dec 4, 2013
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NF is the product...
And yes, 140mm, being the most powerful means it's probably going to improve the airflow.