Torsional Vibration of shafting in general is a very broad subject which can cover shafting of greatly varying configurations that respond to a broad range of excitations. Here we will focus, initially at least, on shafting in turbomachines which are the prime movers for the processes they support.
Factors that distinguish these machines are:
- They must operate reliably for extended periods
- They consist of mostly steel components that rotate on a common axis
- There are no chains or belts in the train
- There is little if any backlash in the train, contributed mostly by gear sets
- By nature they possess very little internal damping
A defining characteristic of torsional vibration in turbomachines is that the shafting is rotationally isolated from the supporting structures along the shaft axis. This means that in many cases torsional vibration can occur at any level without being sensed. Anything that can occur without you sensing it is a risk that you don’t know about and can come up and bite you in the %^(^&%(^.
There are many papers on this subject. Many deal with damage and breakdowns which occurred unexpectedly. It is the intent of this blog for people to share their experiences and concerns regarding torsional vibration. Please feel free to contribute your thoughts. I will provide discussion and answers where I can.
Best regards, R. Whitney