noise reduction of axial fans mounted to sheet metal
noise reduction of axial fans mounted to sheet metal
(OP)
Hi all,
I'm working on a project to reduce the amount of noise produced by two 34" axial fans mounted on top of a small tunnel. The fans are currently mounted to 12 gauge sheet metal, causing the sheet metal to vibrate like crazy. The fans appear to be incredibly unbalanced, just from a simple visual observation after shutting them off and watching them slow down. The area is also very dirty and the blades are caked in dirt and debris, which I'm sure further contributes to their unbalance.
In talking with our maintenance crew, they suggested simply replacing the fans. For reference, this is the model of fan: http://americraftmfg.com/product-lineup/duct-fans/... (B-34-5-TEFC). While I wanted to avoid spending 3 grand to replace them, it still doesn't fix the fact that they are mounted to sheet metal. My idea was to add a 3/8" thick sheet on top of the existing sheet metal to help stiffen up the surface, but I'm sure there are better options I am not thinking of. Any help would be much appreciated.
Thanks!
I'm working on a project to reduce the amount of noise produced by two 34" axial fans mounted on top of a small tunnel. The fans are currently mounted to 12 gauge sheet metal, causing the sheet metal to vibrate like crazy. The fans appear to be incredibly unbalanced, just from a simple visual observation after shutting them off and watching them slow down. The area is also very dirty and the blades are caked in dirt and debris, which I'm sure further contributes to their unbalance.
In talking with our maintenance crew, they suggested simply replacing the fans. For reference, this is the model of fan: http://americraftmfg.com/product-lineup/duct-fans/... (B-34-5-TEFC). While I wanted to avoid spending 3 grand to replace them, it still doesn't fix the fact that they are mounted to sheet metal. My idea was to add a 3/8" thick sheet on top of the existing sheet metal to help stiffen up the surface, but I'm sure there are better options I am not thinking of. Any help would be much appreciated.
Thanks!





RE: noise reduction of axial fans mounted to sheet metal
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: noise reduction of axial fans mounted to sheet metal
RE: noise reduction of axial fans mounted to sheet metal
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: noise reduction of axial fans mounted to sheet metal
Is the entire tunnel "alive" if felt when a finger tip, or just the fan mount top plates, or ????
I'd run the output of a cheap sound level meter on the A scale (http://www.amazon.com/Radio-Shack-Digital-Sound-Le...) into a PC sound card and process the signal with a free FFT program.
Then I'd kind of know the frequency of the sound. If it was not related to fan 1X rotational frequency I would be less concerned with balance and unbalance.
Using the A scale knocks down the lower frequencies so the display will "look" like it sounds, unlike this -
http://upload.wikimedia.org/wikibooks/en/d/d8/Nois...
RE: noise reduction of axial fans mounted to sheet metal
Tunalover
RE: noise reduction of axial fans mounted to sheet metal
RE: noise reduction of axial fans mounted to sheet metal
https://play.google.com/store/apps/details?id=com....
It even averages.
- Steve
RE: noise reduction of axial fans mounted to sheet metal
RE: noise reduction of axial fans mounted to sheet metal
Tunalover