Which fan placement offers the most airflow for cooling electronics?

[garyTheSnail]

TL;DR

Best fan position for airflow.

I have two identical fans to cool electronics within an enclosure. From the two drawings/options, which option offers the most airflow?
Thank you.

 

[russ_watters]

The first arrangement can overcome more pressure, the second arrangement produces more airflow.
https://www.rotron.com/tech-corn/series-and-parallel

 

[DaveE]

The first arrangement can overcome more pressure, the second arrangement produces more airflow.
https://www.rotron.com/tech-corn/series-and-parallel

Yes, this. And you can have some control on the pressure differential with the design of your vents. Higher air velocity isn't going to help cooling too much, what you want is high mass flow (at the critical locations, of course). The answers lie in the pressure vs. flow curves for your fans combined with a rough model of the enclosure resistance, another pressure vs. flow curve.

 

[Lnewqban]

Relocating both exhaust vents to higher positions, option B offers the most cooling effect.

 

[garyTheSnail]

Thank you all for the information.