[|kbn|]

Originally Posted by maxSaleen

This is moving away from the original goal of optimizing a radiator for a specific fan. Cath specified roughly 43cfm of flow with a pressure I'm too lazy to look up. For these given specifications, Caht's design works best. Increasing the frontal area, 180x180, might help performance. Increasing the depth to 100mm would actually hurt performance as it would reduce airflow. Increasing the FPI count might also hurt performance as it would also reduce airlow.

Not if a higher pressure fan would be used

I think we all do. I was excited the first time I fired up a 12cm tornado, but the novalty wore off in about a minute as I began to lose my hearing. Until someone comes up with a maglev/magdrive fan we are stuck with traditional bearings/sleeves and traditional motors. Perhaps deeper fans with more blades and more curvature to the blades would help with back pressure. This is going into territory where I can only speculate.

All of this is beyond me.. Im just suggesting and learning from your comments
One thing is ive not seen a fan which has bearings on both sides of the fan, with the frame on both sides.. would that not help to stabalise the blades and make it more balanced also reducing niose?
Im jut trying to understand this stuff... I mean there are HDDs that spin at 7200rpmand are comleatly silent because of FDB bearings.. could they not be used in a fan?
Then theres the problem of airflow noise... I think lowering the RPM and changing the curvature would lower the noise a very large amount.. and also make the pitch much less annoying.. ive looked on google for stuff on fan design.. anyone found any good sites that explain thi stuff?

Originally Posted by Marci

Half of the noise generated by a fan/rad combi is from the friction of air passing over the fins. You increase the FPI, the noise level increases also. As either FPI or Core Depth increase, a fan with higher pressure is required to penetrate. Most 120mm fans with higher pressure mean higher noise output due to higher CFM. Higher CFM means more air blown over fins means more frictional noise.

Never noticed any increase of niose from placing a restriction on a fan..maybe but I dont think its significant. I think the noise is from the high RPM, much like if you drive in 2nd gear at 30mph, much louder engine becuase of the rpm than in 3rd gear or 4th gear.

Waste of good air... if it's going anywhere other than thru the rad, it's inefficient.

I know.. that was an example of something I realised.. as before I forgot and assumed that the motor would slow down - which it does.. but the effect of air bouncing back is much greater

Sorry for going o/t, Ill start another thread