Learning Forum

[Ana Pereira]

 

Hi,

Thanks for the reply!

I am doing a structural analysis of a stiffened panel, you can see the main details in this screenshot:

The bottom right shot is for the 5th eigenmode, although, the first eigenmode for such analysis can be found on the following figure:

The result above was shown when I selected “5” as the Max modes to find. Although, when I change this input to the value 1, these are the results I get:

So -8.6327e-04 is quite different from -1.2934e-05. What might be the reason?

In addition, I understand that the buckling results are load multipliers and therefore must be multiplied by the applied load. Following this logic, and after having seen the Ansys Tutorial about eigenvalue buckling, I don’t undertsand how the buckling patterns change depending on the magnitude of the applied load, since this analysis is described as being “load independent”. In the figure below, we can see the tremendous change in buckling behaviour between applying a line pressure of 5000 N/mm and 7500 N/mm.

Any guidance you might offer for any of these cases? I’m sorry in advance for such a long response but these are doubts about my master’s thesis that I haven’t been able to get any help with.

Thank you so much for your help!