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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.
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Good to see it's just about right! NLGEOM is already turned with the "Nonlinear Static 3D" analysis type setting in Mecway. Contacts penetrating each other is also because the "Slope of pressure-overclosure curve K" on the contact is too low. It sho…
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OK. Sorry for all the hoops you've had to jump through. The scaling will be more uniform in the next version and it will probably double the size of graphics items above 150% but not at 150%. I see from your feedback that that's too big of a jump.
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The error messages on red items in the outline tree are for Mecway's internal solver, so you often have to ignore them for CCX. Now I somehow can't get that to converge anymore so maybe I accidentally changed something else. I suspect the main prob…
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VMH, I had a look in the code and there's no use of convergence criteria for generating the .inp file. Perhaps you got different results when it didn't converge, where it could potentially give a very different result on each run due to numerical er…
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There are several problems. I'm not sure which one(s) are really important but here's what I changed: Changed the top roller's contact faces from the top to the bottom Changed Glass_Epoxy's shear modulus units from Pa to GPa Suppressed one of the…
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That's right. CCX has a *CONTROLS keyword for convergence parameters. I've never used it and I don't think you should unless you have a very special type of problem. If something's not converging, then tweaking the tolerance often just covers over t…
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The convergence are currently ignored for output to CCX. You would need to specify that as custom step contents using CCX keywords.
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That sounds like a likely reason for not converging. Good to hear you got it working. Yes, use pressure for a follower load. Automatic time stepping is generally a good idea. To turn it on: 1) Right click CCX in the outline tree and click "don'…
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This is a problem. Thanks for pointing it out. You would have to work around it by setting the analysis type as Static 3D to allow entering the data then change to nonlinear for solving. I know this is going to be quite inconvenient sorry.
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That's how it is in version 5. These items are only getting scaled by multiples of 100%, so they don't scale smoothly with the DPI setting. In previous versions, they didn't scale at all. Now they jump up to double size with 150-250% DPI, triple siz…
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Hello Dave 1. It looks OK to me. I would also try a force parallel to the axis (bolt direction?) in case normal pressure causes artificial radial loading which, in real life, might be opposed by friction between the outer rings and the rings in the…
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CCX doesn't seem to use the rotational DOFs in its constraint equations (*EQUATION) so this type of connection doesn't work correctly though it's OK with Mecway's built in solver. I've constrained it so only translational DOFs are relevant and it p…
