Several years ago, I was visiting the Advanced Photon Source at Argonne National Laboratory, and I remember that in one of the working areas there were some large cylinders suspended in the air above the electronics racks by wire. Our tour guide had mentioned that the researcher had been an acoustic engineer and put them up himself to dampen the constant loud drone of the facility. I was skeptical before I walked under it and, despite the area being quite open and unshielded acoustically to the machinery, the cylinders had done a near perfect job of dampening the sound. Now that I've been working in facilities with similar noise issues, I'm wondering if this is a common solution or if there is a name for these simple noise dampening devices?
I don't know if there is a specific name for that. But it is a known fact that sound-absorbing fabrics and foams especially if placed in acoustical focal points of noisy spaces large enough to promote reverberation, will help the attenuating of noise.
These decorative objects have to meet fire and safety codes and be easy to wash and maintain. And they scale and align in a prescribed way. They usually are composed of 3 components:
1 - the sound-absorbing foam
2 - the wireframe structure
3 - the cover fabric which is sound transparent.
There are several manufacturers that help design these devices and sell them.
this is the catalog of one manufacturer:
In music recording studios, those tubular absorbers are common. I hear them referred to as "sound tubes" but I do not know if there is another name for them. I recommend you look at some sales literature for manufacturers of acoustic treatments for sound recording facilities to find out.