More and larger cooling fans

[wrcsixeight]

Way too weak to yield a meaningful effect. Look for a Spal of at least 12",
better 15" diameter which will deliver ten to fifteen times the air volume
and also survive rain. As always use the proper gear for the application.
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I never did, nor would recommend using a small server fan in front of, or behind an automotive radiator.

My applications for these fans falls strictly into 'other', and I almost always use the largest diameter fan I can squeeze into the application, and speed control via voltage from minimum whisper quiet, to screaming banshee intolerable for long noise levels.

I linked the 254 cfm fan only as an example of a powerful 'computer' fan, considering its 120mm diameter size and 38mm width.

I brought up these fans only to share my considerable amount of experience regarding experimenting with various fan designs. The variables being blade/impeller design, fan rpm, amp draw, distance from restriction, and efficacy when pulling vs pushing configurations, all of which are valid points in the consideration of adding additional fans, all of which that were apparently lost on you, making any further attempts at enlightenment, both pointless and futile.

 

[930.engineering]

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Is it my fault computer fans are that limp? Are you sure this is a reason feeling sore?
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[Jim K]

Here is a good size cooling fan.

 

[wrcsixeight]

Nah, I.m irritated with myself, as even with all the clues you provided as to your limited intellect, I thought it was possible to help you become better informed on a subject I am very experienced with. I'll waste a bit more time and then cut my losses and wish you good luck.

You are apparently comparing a grape to a peach.

Lets compare a 4 grapes to a peach.

The 15 inch Spal fan, VA18-AP10/C-41A * 16"S/12V covers 51.15 square inches, and claims 1074 CFM
4 of the delta 'computer' fans I linked, side by side, would cover 59.66 square inches and 4 together will move 1017 CFM.

So yes, the bigger Spal fan does indeed move a bit more air, when there is NO restriction to airflow, the restriction being the AC condenser and radiator fins themselves, as well as the shroud and fan(s) on the other side.

The higher RPM and the rather huge static pressure rating of the 4 smaller fans combined, will likely push more air at a higher velocity through the same restriction, and perhaps remove more heat than the larger fan.

4 of the delta fans in parallel, will consume about 12 to 13.5 amps at 12vdc.
The 15" Spal fan claims it needs a 25 amp fuse @ 13v.

If the Spal draws 20 amps continuous, that makes the computer fans about 35% more efficient in terms of the amount of air moved, for wattage consumed.

Note: I am not advocating for using multiple brushless high power 'computer' or server or axial fans in an automotive radiator application.

But if I were, stacking the high power Delta 4.75" 'computer fans side by side into a well designed shroud, and one atop the other, I could likely stuff no less than 16 of them onto the average size radiator, for 4050+ cfm, which I believe is right on par for the biggest most powerful electric fan claimed CFM radiator shroud available.

Note that these 254cfm 4.75" Delta fans are so powerful, that putting two side by side causes them to fight each other as they scavenge and throw so much air, so better to space them a bit further apart, and even spaced apart fitting 16 or more of of them in front of or behind the average radiator would hardly be impossible.

I would not want to have to listen to 16 of them at once when fed 12 to 14v, one is loud and annoying enough.