Need restricted motion in heave only for a floating object
I would like to simulate a floating body in a wavetank under irregular wave conditions. I need to put constraint on the motion of the body in X and Y direction. The body should only move in Z direction (Heave motion). How do I restrict the motion of the body in only Z direction?
Debug Trace
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Comments
Did you attend the SPH workshop ?
If so I think you can use coupling with project chrono in the 4.3BETA to achieve your goal.
If not, either you can wait for the release of 4.4 (and coupling with project chrono) or you "dirty" model a mechanical articulation that can mimic what you want.
It's not pretty, but it can do the job. I've been able to model hinges that way with no problem. I use the default SPH solid modelling (no DEM), and keep in mind that a floating can have deported pieces linked to it (no need for the particules of the floating body to be physically next to each other). Also flooding the "articulation" was a good idea in my case to "calm" the floating and prevent it to go crazy and eventually going outside the simulation.
Here is an example of what I did for an hinged anti-backflow system. The articulation is deported on both side of the simulation to not disturb the flow. The two boxes are filled with water.
Hope that helps you.
T
Do you have any particular reason for not using the DEM approach?
Its seems to me that this is easy to use. For now the devs have included xml examples, I think they will update the wiki also and maybe the pdf guide to xml...
About DEM, no other reason than one of the devs suggests it to me.