I was curious if anyone has done testing on what's the best way to layout a an array of fans. I have 3 200mm fans on my case that push air through my radiator.
I always wondered if it's better to stack the fans on top of each other or lay them side by side.
Stacked like the attached image, not the radiators just having 3 fans in that layout. If you have 3 100cfm fans, are you getting 300cfm or just 100cfm?
You'd just be getting 100cfm, as the fan blades would be spinning at the same rate. It only works in that picture above because the radiator fins obstruct the airflow, so adding the extra fans keeps it more consistent. Even so, what's done in that picture is overkill.
Stacking the fans so there is no space between them doesn't help unless the blades are rotating in opposite directions (but still pushing air in the same direction).
"Stacking" fans while leaving a little space between them actually helps airflow greatly in my experience. For example, putting a Hyper 212 style cooler on your CPU and then adding another fan next to it to push the air that's coming off the CPU from the pull fan out of the case.
With air cooling, first figure out how to set up a positive or negative airflow configuration, then maximize the effectiveness of the fans by choosing their location carefully and trial and error.
I've seen that video couple of years ago and where got the idea but turns out it's a troll video. If I ever meet him in person, I'm going to smack him over the his head.
if you are talking about push/pull vs pushpull in the sense that should you put a fan on each side of a radiator or just one side to have a fan, than the answer is simple. if you just have pull (side by side) you will get good performance but if you put them in pushpull (on top of each other) that is one fan on each side of radiator per fan slot you will get slightly better performance but it will be marginal maybe 1-3c. what this does is ensures airflow and static pressure to be closer to the theoretical max for the fans at any given RPM which in the real world gives us this small boost. If you have 200mm fans and you want more performance just get more powerful fans if you are able 180mm fans often have much faster RPMs and more powerful motors. stacking fans ontop of each other without a radiator or fin array between is totally wasted. if you spaced them out some you would again get closer to theoretical max performance of the single fan but never more.