Here is another topic that will surely put you to sleep. Or, maybe it will keep you awake during the night.

I have long been fascinated by the impact of vibration and noise in refrigerant piping. As you will see in the files below the manufacturers are aware of this and are offering some general guidance on this particular subject.

In general terms, the problem is associated with the acoustic velocity (speed of sound) of the refrigerant for the specific operating condition. The other important aspect is the frequency of the gas pulsations from the compressor.

Screw compressors should be treated differently than reciprocating compressors since the gas pulsations are different for both types and are also dependent on rotating speed.

By determining the above you can then calculate the "piping lengths" to minimize the impact of vibration and the resulting noise.

The information below is not a set of documents that provides all of the information, but they are sufficient to show an interesting concept to consider.

http://www.carlylecompressor.com/Fil...f?SMSESSION=NO
(740 kb)

http://www.bitzer.de/_doc/s/st-630-1.pdf
(323 kb)