More case fans, or big case fans?

[FineVisionz]

More smaller case fans, or a few big case fans?

[Fulgrim]

Depends on what case you currently have, and your fan setup.

[scaryjam823]

More smaller case fans, or a few big case fans?

http://www.tomshardware.com/forum/322958-31-smaller-fans-cooling

 

"Area a circle A = Pi times r squared

 

A 200 mm fan has 0.0314 square meters area [ believe me I did the math ]

 

a 140 mm fan has 0.015 square meters , but there are two of them so 0.030 

 

The single 200mm fan has more area [ just] than two smaller fans , and even more again when you consider that all three fans have a similar size hub sizes and you lose that area twice with the smaller fans .

 

Also if a 200 mm fan is spinning at the same speed as a 140 mm fan the tips of the blades are moving much faster . This is part of the reason why a larger fan doesnt have to spin so fast to move more air . A bonus of that is that it then makes less noise 

 

One big fan , not two small ones"

 

"Hmm guna do the math and write it out here to see the outcome

 

Pi (3.142) x Radius ((70mm)140mm fan) Squared

Effectively 70x70x3.142

= 15395.8

Now x2 (because there would be x2 140mm fans) 

= 30791.6

 

Ok so now the 200mm fan:

 

Pi (3.142) x Radius ((100mm)200mm fan) Squared

Effectively 100x100x3.142

= 31420

"

 

To add, a larger fan will spin slower and be quieter than smaller fans. I have the largest fan sizes I can have in my case. 4x200mm, 2x 140mm, 2x 120mm, 1x80mm, 1x120mm. It's pretty quite and stays cool, it was  even quite when I just had the 200mm fans installed.

[TheMcSame]

Personally, I'd go for more unless you can fit 180+mm fans. The difference between 140mm fans and 120mm fans is next to nothing, in some cases 140mm fans don't perform as well as 120mm fans.

[FineVisionz]

 

http://www.tomshardware.com/forum/322958-31-smaller-fans-cooling

 

"Area a circle A = Pi times r squared

 

A 200 mm fan has 0.0314 square meters area [ believe me I did the math ]

 

a 140 mm fan has 0.015 square meters , but there are two of them so 0.030 

 

The single 200mm fan has more area [ just] than two smaller fans , and even more again when you consider that all three fans have a similar size hub sizes and you lose that area twice with the smaller fans .

 

Also if a 200 mm fan is spinning at the same speed as a 140 mm fan the tips of the blades are moving much faster . This is part of the reason why a larger fan doesnt have to spin so fast to move more air . A bonus of that is that it then makes less noise 

 

One big fan , not two small ones"

 

"Hmm guna do the math and write it out here to see the outcome

 

Pi (3.142) x Radius ((70mm)140mm fan) Squared

Effectively 70x70x3.142

= 15395.8

Now x2 (because there would be x2 140mm fans) 

= 30791.6

 

Ok so now the 200mm fan:

 

Pi (3.142) x Radius ((100mm)200mm fan) Squared

Effectively 100x100x3.142

= 31420

"

 

To add, a larger fan will spin slower and be quieter than smaller fans.

 

 So lets say if you have a 230mm fan at 100% and a 140mm at 100% the 230mm fan will have the more airflow... correct? 

[Cheese4395]

So lets say if you have a 230mm fan at 100% and a 140mm at 100% the 230mm fan will have the more airflow... correct?

Theorically correct because like he said more area so to push the same amount as two 140s it would spin slower. Logically it makes since if you pushed it even more it would push more air. The only barrier to this is making sure that top rpms are the same because otherwise it won't be exactly what you think. Ie smaller fans spin faster and have a higher top speed while larger fans spin slower and have a lower top speed and then you'll never be able to compared them because at 100% they won't be spinning the same speed.

[scaryjam823]

 So lets say if you have a 230mm fan at 100% and a 140mm at 100% the 230mm fan will have the more airflow... correct? 

As @Cheese4395 said,if they are the spinning at the same rpms then yes the 230mm will push more air. Now keep in mind larger fans typically have lower rpms than smaller fans, meaning while the larger fan has potential to push more air, it may not. But that's entirely dependant on the manufactures speed rating and what they feel is adequate. But on the same side of the coin the larger fan will push the same air at a lower rpm compared to a 140mm at a higher rpm. Difference being the larger will be quieter at the same rpm. If the smaller fan has more rpms then it will push more air, but only because it can spin faster not because it is more efficient. I take larger fans over smaller fans.