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Mesh keeps folding, Help?

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Old   July 20, 2012, 13:03
Default Mesh keeps folding, Help?
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Angus Bishop
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Ok i suck , I'm trying to set up a rigid body simulation of a hollow cylindrical shaped hull of a boat , although i am stuck with a few things , as ever, help makes you awesome.

I keep getting an error message saying that my mesh has folded or something like that. This goes away instantly as soon as i turn off the motion parameters.

Are there particular faces i need to set up that link with the mesh?

Additional pics can be provided
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Old   July 20, 2012, 18:18
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Glenn Horrocks
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It is MUCH harder to do this type of simulation as a rigid body. It is much easier to assume the floating body position and see what lift/drag you get at that position. You can then refine the body position if the lift or drag say it should be adjusted a bit.

Then the simulation becomes a series of fixed mesh simulations. This is much easier than a single rigid body motion simulation.
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Old   July 23, 2012, 04:08
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Thanks for the reply , but i'm trying to do waves too, also trying to find the floating body position and a multitude of other things , so i need to learn how to do rigid body
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Old   July 23, 2012, 04:34
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Kolja Müller
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have you tried the buoy tutorial and mesh stiffness?
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Old   July 23, 2012, 04:53
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Yeah my mesh stiffness is an enormous number , Unless it should be small?
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Old   July 23, 2012, 06:46
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Kolja Müller
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yeah, pretty sure. otherwise your cells vanish = folding, no? pretty sure youll find your answer in the buoy tutorial..

cheers
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Old   July 23, 2012, 07:36
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Are there any particular design points that change by using a 3d problem?
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Old   July 23, 2012, 11:29
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Ah i think the issue is the Timestep size , Am putting it down to a lower value, It made a difference on the Bouy tutorial.
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