I don’t think it matters very much whether you set these fans blowing in vs out; it should be symmetric?
It is not symmetric: Blowing is not the opposite of suction. In particular, it doesn’t exert negative force in the ideal case, as demonstrated in the Feynman Sprinkler experiment.
This is not the same as in your example, as the ventilator is stationary, but you probably notice little “negative” wind at the back of the ventilator.
From a practical point of view I would expect the pull fan to better ventilate the corners of the room. On the push side the flow is more directional and I think with a push fan you’re more likely to end up with turbulent flow in the corners which would noticeably slow air transfer from these regions. From this point of view it’s possible that the 2 x pull configuration may actually be better than 2 x push + 2 x pull but I’m no expert.
Of course if the air speed is low then the difference will be minimal.
It is not symmetric: Blowing is not the opposite of suction. In particular, it doesn’t exert negative force in the ideal case, as demonstrated in the Feynman Sprinkler experiment.
This is not the same as in your example, as the ventilator is stationary, but you probably notice little “negative” wind at the back of the ventilator.
From a practical point of view I would expect the pull fan to better ventilate the corners of the room. On the push side the flow is more directional and I think with a push fan you’re more likely to end up with turbulent flow in the corners which would noticeably slow air transfer from these regions. From this point of view it’s possible that the 2 x pull configuration may actually be better than 2 x push + 2 x pull but I’m no expert.
Of course if the air speed is low then the difference will be minimal.