Effects of Grill Patterns on Fan Performance/Noise

[a111087]

I wanted to cut out my grill, but wanted to find out what is their effect before I actually commit to it. I found a great review, which I think should be seen by everyone.

Link to the complete review: http://www.pugetsystems.com/labs/articles/Effects-of-Grill-Patterns-on-Fan-Performance-Noise-107

Test grills and results:

 

[newtekie1]

Surprising, I would have through the mesh would be the worst CFM wise. It would have been nice if they tested with a filter in place as well. I personally use filters on my main rig, but I have to, because the only place I can put it in the room is on the floor and I have 4 dogs. Without the filters the case fills with fur in a week...

 

[a111087]

Surprising, I would have through the mesh would be the worst CFM wise. It would have been nice if they tested with a filter in place as well. I personally use filters on my main rig, but I have to, because the only place I can put it in the room is on the floor and I have 4 dogs. Without the filters the case fills with fur in a week...

Yeah, the mesh is getting pretty close to being the worst as far as CFM goes.
I actually asked the author to do another review and include air filters. So, will see...

 

[sneekypeet]

Saw a bunch of this data from SilverStone at CES. It may interest you to look at the fan grills on GD07 and 08. That is the design they found to perform the best for them. Just very interesting as to what sorts of cuts and adjustments need to be made as to just not increase the dBA levels. Something most filters don't even take into consideration, like most of the ones tested in the OP.

Only thing is, I don't think they sell the filters without the cases.

 

[newtekie1]

Yeah, the mesh is getting pretty close to being the worst as far as CFM goes.
I actually asked the author to do another review and include air filters. So, will see...

Yeah, but really, even with the mesh, you are only loosing 2-3CFM, I can live with that if filters give about the same drop.

 

[MT Alex]

My 700D has the honeycomb top where my 360mm rad is mounted, and it's loud as hell, very annoying. I've always wanted to cut it out, but I don't think black wire grills would look as nice.

 

[entropy13]

Only thing is, I don't think they sell the filters without the cases.

Are the filters Silverstone sells (two kinds, magnetic and loose swirl, and screw-on and honeycomb; magnetic only comes in 120/140mm while the screw-on have 80/120/140mm sizes) different from the filters you are talking about?

 

[FordGT90Concept]

Figured wired would be best and turbine would be worst. Turbine has the most surface area blocked and blocked creates drag and drag is bad.

Wired is awesome because they are round which tends to reduce drag. If all styles were rounded, the one with the biggest holes would win.

 

[a111087]

the one with the biggest holes would win.

that's what she said

 

[a111087]

found another review that also tests air filters (and even fabric softeners):

Complete info: http://www.xtremesystems.org/forums/showthread.php?209801-Some-Wire-Mesh-Filter-Fan-Grill-Testing...

also, how about we sticky this thread?

 

[LAN_deRf_HA]

I hate the noise when I do a cheap Rosewill build. They use circles sized somewhere between mesh and the honeycomb and it makes for bad noise, and it's built into the case.

 

[a111087]

Yeah, with all the progress that we see in computer industry, you would think that companies will wake up and start cutting the grills out to save us some time and effort (and metal for them to recycle).

 

[Completely Bonkers]

I thought all enthusiasts cut out stamped grills and replaced with wire!

Note that all these results are fan and RPM dependent. It would be good to see a review of performance at different fan speeds.

I'm also doubting the real-world accuracy of the airflow CFM tests. I'm pleased they made a best effort at measuring it... but I don't believe that a baffle covering 50% of the "open space" e.g. angled slats, turbine and mesh could deliver 85-93% of the CFM airflow. That just isnt right. I think there are some problems with the 120mm to 80mm funnel technique that they used... which has painted a misleading picture of how these grills are really affecting airflow. Anyone with even an armchair understanding of fluid dynamics would know that changing the "r" will SIGNIFICANTLY affect airflow. Isn't the relationship r to the power 4? So between 120mm and 80mm there is a factor of 5-ish difference in airflow. Pushing 120mm airflow through 80mm means that the resulting changes in forced air-pressure/resistance might totally screw up the observed measurements.

Anyone interested in this might want to look here http://en.wikipedia.org/wiki/Airway_resistance just to get an idea of the issues.

Far better if they DID NOT funnel from 120mm to 80mm but had a 120mm measuring instrument... and failing that... 2x 80mm measuring instruments... and a circle to a figure of 8 tube adapter/modifier.