Position dependent (hydrostatic) loading in dynamic simulations


Dear all,


currently I want to simulate the transient oscillation of a floating body until its stable state is reached.


In a first attempt I used Sol129 - Nonlinear Transient Response and added gravity and a hydrostatic pressure loading to the under-water surfaces. However, this does not work, since the liquid surface, which can be defined in the loading definition, does not update over the iterations. This causes a constant acceleration and hence a linear accelerated displacement motion. Of course, creating different subcases does not work as well.


A possible solution would be to simulate the hydrostatic pressure by springs in the .fem file, but this would be very complex to implement - if even possible.


I will also have to add some kind of damping, but this should not be too difficult.



Is there an easy solution for the simulation of these kind of problems or do I need to switch to NX Motion (which rises the question of how to implement a hydrostatic loading there)?