The correlation between vibration and flow rate

tony_engin

Hi all.
Suppose I am increasing the flow rate of the water through a sprinkler or a tube, there should be some vibration induced by this increment of flow rate, right?
On the other hand, if I decrease the flow rate of the water through the same sprinker, there should also be vibration induced by this decrement of flow rate, isn't?
So, in general, which type of vibration would be greater in these two cases? Intuition? Analytical equations? Experimental results?

FredGarvin

In a short response...it all depends. What exactly are you getting at here? Describe your system in more detail. The flow induced vibrations are going to be very dependent on the kind of flow you have, the plumbing system itself and other factors. It also depends on what vibrations you are refering to.

Intuition should tell you that as the flow rate increases, the frequency of the vibrations as well as the amplitude should also increase if we are talking no system resonances or structural resonances. If you start to throw in things like cavitation or immersed bodies in the flow stream, all bets are off.

tony_engin

Actually it is a pipe flow problem.
If the flow rate is constantly increasing, will it cause more vibration on the pipe than decreasing the flow rate constantly?