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Victor
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You have to switch to nonlinear analysis type for it to be enabled. That tends to be quite confusing especially since CCX automatically turns on geometric nonlinearities when you use a plastic material anyway, so I hope to clear this up in the next…
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There's "line pressure" which sounds like what you mean. Is it this?
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Not with Mecway's built in solver. If you use the 3rd party CalculiX solver, you can do this. You'll have to specify the displacement-time pairs by entering some commands though and not as a formula. The PipeClip.liml sample on p92 of the manual sh…
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They are already displayed as arrows. Can you clarify what you mean?
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It's because some environment variables aren't set. Either: - Use ccx.bat that's installed along with CalculiX, rather than ccx.exe. Beware that with a batch file, if you shut down Mecway while CCX is running, it can continue running silently in th…
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So this is a CCX bug in reading .inp files with CRLF vs LF?
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The modes are mass normalized where the mass matrix is that of a material of 1kg/m^3 density. That's just the default that the eigenvalue solver produces and there's no compelling reason for it. Though I know or someone who used that fact to do thei…
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1. Version 6 will have some more powerful local refinement tools for manual meshes. 2. That sounds like substructuring. Not something I give a high priority to since it's an optimization that could complicated to use.
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Hello thachmonkey It's relative - the pressures are scaled by an arbitrary factor that's different for each mode. The actual amplitude would depend on the source of sound and the damping in the room, neither of which are modeled by Mecway.
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Good point. It's using the Abaqus format with *BEAM SECTION but should be *BEAM GENERAL SECTION for CCX as you say. In the mean time, you would have to define this section type manually using custom model definition in Mecway.
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Although I haven't checked this case on Linux, the difference might not be anything to worry about. It could be that two same-frequency modes switched order or that they're physically the same mode but rotated one segment around the axis. Do you se…
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Yes, that's the general idea, though in this case I think it's a particularly difficult type of buckling - a toggle mechanism (aka "snap-through buckling") which means it can't be solved with the linear buckling solver which only does bifurcation bu…
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Still on my pet theory of buckling. Your pictures gave me an idea. That change looks a lot like a toggle mechanism where a straight beam "snaps" through 0 degrees while being constrained from horizontal displacement. This type of buckling is traditi…
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Yea, that's something I expect to leave to a future GUI redesign.
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That's a nice chart Simon. It really shows how much better kwip's CCX 2.10 is! It would be helpful to see your meshes because the topology has a huge effect on performance as shown in my table further up this thread. Two models took 4 minutes and 1…
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I wouldn't set any convergence tolerance. The default (if you leave it blank or 0) is almost at machine precision so it's pretty much always going to be correct. Setting anything else is just to speed up convergence or get it to converge if it doesn…
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Sounds like a good idea. I've added it to my list.
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I've considered this but what worries me is that the maximum is almost always a stress concentration which isn't really what's interesting or correct. So then it would need another "2nd highest maximum" flag as well. Come to think of it, perhaps it …
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Right mouse button pans. If that's not comfortable, you can change it to the middle button in Tools -> Options. The main reason for the rotate and zoom buttons being on the toolbar is for people with no mouse wheel or middle button, such as a tra…
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Thanks for the suggestions. Both on my list now.
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A bit of a mystery. Changing to 2D elements, it extends the full 28mm (attached picture and .inp file). I wonder if there's some kind of instability because of compressive hoop stress? To investigate further, I'd revolve the mesh into 3D similar to …
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Thanks everyone for bringing this up. I find it won't work or show any output if you use ccx.exe. Instead, use ccx.bat which sets some environment variables. With that, I was able to solve the pipeclip example. It might be because it depends on dlls…
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Could you please attach a complete .inp file? This one refers to some missing .msh files and I'm not used to using .fbd if that's generating them.
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When I run ccx-only.inp, I also find the linear model has higher Y reaction force (1.518) than the nonlinear one (1.32), but approximately the same displacement (magnitude 1.082 compared to 1.080). That means the linear model is stiffer than the no…
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Oh yes, that would be more sensible. The equation is really ugly.
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I've managed to get force to solve OK, but as Sergio said, it's a lot harder than displacement. I did it by seeing what kinds of incorrect displacements the non-converged solutions gave and constraining them: - Merged some nodes of the top roller w…
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Have you tried, in the outline tree: Solution -> Components -> Right click Layer 4 -> Hide? That should hide that component in a CCX solution in version 5.
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It probably needs to be increased further. I turned it up to 1,000,000 GPa/m. "slope of pressure-overclosure curve" is a kind of stiffness. When CCX detects a pair of faces have touched each other, it connects them with stiff springs to prevent them…
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Bonded contact won't do that because it only connects the beam's node to a point on the master surface, rather than the whole surface. The poor-man's way would be to use multiple beams. Or you could probably do it using CCX's *RIGID BODY but that m…
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The XYZ pressure load isn't currently supported for exporting to .inp.
