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Victor
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What does the convergence graph look like? Is generally decreasing or oscillating between identical values? If there's no graph yet, it might be stuck on the first iteration. It's possible that the model is big enough to cause the solver to use the…
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The displacement is smaller with 1E10 as you'd expect. See attached picture. If K is changing the result, then it needs to be bigger. Make it as large as possible without causing it to fail or take too long to converge. You might have trouble with …
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It works OK for me. I used this plate material: *MATERIAL,NAME=Cplate *ELASTIC 1.0000E+08,0.3 and it caused double the displacement at the middle of the plate, compared to the original plate material with E=1e9.
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To be a bit more specific - in the *STEP section Sergio mentioned, use *BOUNDARY to specify a displacement in the X direction that moves the plate. Also remove the existing zero X *BOUNDARY constraint on it.
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That's beautiful. Thanks for the post.
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I think the problem is caused by an interaction between the extremely high stiffness elastic supports and the Rayleigh damping on the same elements. I solved it by reducing the elastic support stiffness on the surround to 10^12 Pa/m. I didn't notice…
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disla: It looks like you have Mode superposition method turned on in Analysis settings. Without that, it doesn't have those errors. suktan: I haven't worked out what's wrong yet. If I reduce beta, the problem gets pushed back to later time steps bu…
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Not with the internal solver, sorry. You can get it to skip time steps uniformly with Decimation number of time steps under Analysis settings. For example, set it to 10 to get only 10 uniformly spaced steps, which would include a few at the end.
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It works OK for me. Can you attach the broken model to reproduce the problem?
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A rule of thumb for slope of pressure-overclosure curve is (Young's modulus / thickness) * 10 That should converge OK, then you can increase it by a factor of 10 at a time if penetration is too high. Too low and you get large penetration. Too high…
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The hole tool isn't very smart so you can't use it quite as freely as in CAD. There's no special process other than selecting a node and using the tool. But the node you select should be part of the surface of a solid or shell, not interior to a sol…
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Thanks for the pictures but I somehow still don't understand, sorry. If it's merging too many nodes and damaging the elements, you should be able to use a smaller tolerance. For meshes where I have no feeling for the scale, I usually zoom in to wha…
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Merge nearby nodes is supposed to work with 0 tolerance if the coordinates are identical. Maybe the last digit got changed when importing through .unv? To confirm they're identical in Mecway, select all the same-coordinates nodes and open Node coord…
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No problem, I'll try to be a bit more specific. 1) No need to look in the .frd file by hand. CGX and Mecway can both display stress. I don't remember a lot about CGX but they should be alongside displacement in a menu somewhere. You can also open t…
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Two reasons: 1) The thickness of the voice_coil part is different on the two models - 2 mm and 5 mm. That accounts for some of the difference but not all of it. To find this, I compared their volumes using Tools -> Volume and that showed the ful…
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I can see stress (on the order of -1e4 at time 4.4e-5) and the rings do compress as they make contact as well as penetrating, which is normal. So at first glance that seems OK. Do you find there's no stress data in the .frd file or that it's too lo…
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No, sorry. Though you can right click the graph and use Export to CSV file... then open it in Excel to graph it differently.
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I see. Mode 1 is missing in the 1-segment model and both have the 279 Hz mode. This does look like a problem and it seems to be something to do with the frictionless support on the tri6 element at the center. I'll look into it further to see if it's…
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Hello. Could you attach the 6 *INCLUDE files too? You might also try the CCX forum: https://groups.yahoo.com/neo/groups/CALCULIX/info
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It looks reasonable for the rubber surround to have the lowest frequency mode because it has a high mass and low stiffness compared to the other parts. Or is it the shape of the deformation that's the problem? Beware that modal vibration won't find…
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No, you shouldn't scale the density because the mass will be reduced in proportion to the volume. But you do need to scale the force down since you're only modelling a small part of the structure along with its small part of the force.
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Mecway still doesn't do that, sorry. I don't know of other ways.
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Two problems: 1) The elements at the center are collapsed quadrilaterals that are shaped like triangles, and all their center nodes are disconnected. To correct it, drag to select all 80 center nodes located at (0,0,13 mm) then use Mesh tools ->…
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Short answer: Ramp the X displacement by changing it from "-10" to "-10*t". Otherwise it tries to jam it into the full 10 mm displacement on the first time step and leave it there, but it somehow has trouble with that. Long answer: This is a case w…
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Is this just with kwip's one or in general? Normally, it should do that if you turn on Quasi-static in Analysis settings and specify the time step information.
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The 3 springs are to constrain the 3 degrees of freedom of the cylinder. They have pin joints at their ends so you need several: * The spring parallel to Z prevents rigid body motion in the Z direction. * The spring parallel to X prevents rigid…
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Automesh 2D/3D doesn't currently support Gmsh, sorry.
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The red item in the outline tree indicates an error. Right click it, and What's wrong to see the error message, which say to add a thermal stress "load". In there, you set the reference temperature (I guess 0 K) and all the other nodes without a tem…
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I don't know why CCX 2.10 didn't work. According to the manual, it's supposed to have a blank line. Maybe a CR/LF problem? CCX 2.13 requires a decimal point after the spring constant so it might fail because Mecway doesn't include that - maybe chan…
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The model always has to be fully constrained or it won't find a static solution. At the first time step, before it makes contact, the cylinder is unconstrained. You can solve it by putting weak springs on it to keep it from flying away until the co…
