Hydrodynamics

[mathias_peron]

Hi everyone,

As I'm modelling a water tower in a seismical region I neet to take into account the ovement of water during the seismic analysis.

I have found very interesting topics on the forum and very interesting articles before to post here.

I would like to use the Housner's model for elevated tank and I'm following what have been done before here: http://forums.autodesk.com/t5/robot-structural-analysis-forum/how-can-model-hydrodynamic-pressure-on...

I still have few questions:

- When setting the convective mass (mass on node in Robot), I understand that it needs to be only in X and in Y. But when setting the impulsive mass (that is the mass that doesn't move), don't we need to set it in Z as well?

- Can the impulsive mass be set exactly like the convective mass but with bars with infinite stiffness?

- Do I need to check the box "Apply to all cases" when setting the masses?

Thank you in advane and have a nice day!

Mathias.

[Artur.Kosakowski]

You don't define forces of inertia for a modal case. For a modal case you can define added masses (which influence eigenfrequencies and shapes of modes) but you can apply body forces to these added masses for static analysis.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[mathias_peron]

Thank you.