Modal analysis of a part submerged in water

General Questions
1

Is there a way to create a modal analysis in PreProMax of a part submerged in water? It would be something like the attached video.

:gear: ANSYS Tutorial: Modal Analysis of a Submerged Beam (Modal Acoustics) :droplet: - YouTube

I have a situation in which the water damping may be important for the resonance frequency, and it must be analysed.

Edit: Due to size of the model, it would be interesting to work with shells. In Ansys, it only work with solids.

2

Acoustics are not available in PrePoMax. Some basic implementation is present in CalculiX, so you may ask on the CalculiX forum. It uses the *HEAT TRANSFER procedure by analogy, and there are even FREQUENCY and MODAL DYNAMIC parameters for it. However, this is only helpful if you need pure acoustics, not a coupled acoustic-structural problem like yours.

There’s also preCICE library, which allows you to couple CalculiX with OpenFOAM for FSI.

However, I would consider using Elmer instead - it’s really good at multiphysics and can handle acoustics. Code_aster may work for modal acoustics too.

Of course, what you can do directly in PrePoMax is apply a damping coefficient in modal analysis to account for the fluid.

3

Thank you. I will have a look in both Elmer and possible simplifications in PrePoMax with damping.