When we are doing modal analysis, how many mode should we extract? For complex piping system with thicker wall and less diameter the no of modes to be consider is a difficult task. How can I define upto how many modes should I evaluate for the modal results and check it with external excitation.(adsbygoogle = window.adsbygoogle || []).push({});

I am surprise there is no clear cut answer to this till now, as far as I know and I got. There are very few documents where they have written the mass participation factor, and it's direction, external excitation direction and mode shape determine the no of modes we have to consider. As far as my understanding, I also think like that only and do the same.

But there is a little bit confusion with my friends, who told me only first few modes (for piping four modes) is need to examine for resonance, no need to go for higher modes even though mass participation factor is high enough!!!

And can anyone tell me for complex 3d geometry, is that the nodes of vibration always lie on the geometry itself??

And is it possible that the amplitude at higher modal frequency can be higher than that of lower modal frequency??

And for continuous systems how many fundamental frequency are there??

I am seriously looking for it's answer. Please help me.

Thanks in advance...Lot's of love.....

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# Mass participation factor and it's role in modal anlysis

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