Resonance modes in cylindrical open steel tubes

[Pipedreamers]

Hi Fellows,

I like to ask for some help here. I am trying to calculate
the resonant frequencies for a sample of an open stainless steel
tube, free and mounted rigid on one end.
I have done some measurements with and spectrum analyzer
and got a couple resonance peaks.
My goal with the calculations is to predict the resonant
frequencies (or modes) on stainless steel tubing with
different dimensions.
I have encountered some difficulty to find the equations
to solve such problem.
Is there some software available I could use to solve this ?

Thanks

 

[GregLocock]

Measure with multiple accelerometers measuring radially.

You'll run into probelsm with this - the modes will rotate until the accelerometers are nodal, so a non contacting method, eg doppler laser, may be more appropriate.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[Pipedreamers]

Wow, this get's really deep into it, unfortunately I have no means to follow up on such sophisticated setup.
I guess that's as far as I can take it with this.

Thanks

 

[GregLocock]

OK.

One way to eliminate acosutic modes is to build an enclosure around them and flood it with CO2.

If the modes are acoustic the frequency will change.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.