How do I produce meaningful displacement displacement plot for a frequency analysis simulation?

As I transition to SimScale, I am attempting to solve a problem for which I know the solution to see if I can recapitulate the result with the new (to me) software.

I am modeling a small linear-elastic cylinder made out of a custom material (Young’s modulus 57.1 kPa, density 1000 kg/m^3, and Poisson’s ration 0.495). I am trying to determine its eigenfrequencies so that I can match them with the known theoretical modes of vibration.

To do this, I created a frequency analysis simulation: linked here

The problem is that when I turn on the “displacement” filter in the solution field, I get totally nonsensical-looking results. An example is shown below. Cylinders like these have many interesting types of eigenmodes (axial compression, longitudinal bending, etc, etc,) and I would like to be able to see which frequency corresponds to which of these modes. This does not appear to be a real mode! How do I fix this issue? Is this a problem with my mesh/how I posed the problem, or am I simply not post-processing the results correctly?

Thank you!
Ben

Hello blevyblevy

thanks for sharing your project and reaching out to us here in the forum.

The issue of your view is the scaling of the motion.
We see this issue often when large motions appear for eigenmodes analysis.

when setting the scaling value to 0.01 you can see that a slightly more realistic shape appears.

Unfortunately, this doesn’t work for all modes.
Decreasing the length of the cylinder / or increasing the stiffness of the part should help in order to reduce the motion range of the eigenmodes.

Best regards
Sebastian

Thank you very much for the reply. Unfortunately the results still are so wacky as to be uninterpretable, even with the scaling factor set to 0.01.

With other software I have been able to produce results such as the plots shown below. Is there any way to replicate this with SimScale? I work exclusively with soft materials, with Young’s moduli less than 100 kPa.