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Victor
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All IGES files have this problem with Mecway. Please use STEP instead. IGES support is only really there for very old CAD software that somehow doesn't export STEP. I might remove that in future versions.
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Thanks for this suggestion Steve. I'm trying to work out a cohesive way to include rigid body type features for bonding a beam to a whole surface, pivoting joints between solid mesh parts, and possibly fastener spiders. So loads and constraints dist…
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You know, I'm not sure. It might simply be a lack of tests. They seem to work if you switch to Static 3D to set them up then back to modal vibration to solve. I'll look into enabling them properly.
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Thanks for the suggestion Eduart. What I'm thinking about for that problem is named folders which you can use to group items into. Would that work just as well for you?
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CCX has some error estimates. See the CCX manual for details. I don't know much about them though. There's a rule of thumb to not have the stress change by more than 10% of the whole range over a single element, which means no more than two colors …
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You can define a nonlinear stress-strain curve by entering the CCX cards under CCX -> custom model definition. There's an example of that in the manual section 14.1 Custom model definition. I don't know about nonlinear Poisson's ratio. There are…
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It's not just the reference values, but some of your results don't seem to be converging at all, such as σ_eq,s and σ_sθ which decrease with refinement until local refinement where they suddenly jump up to near the values from the coarsest mesh. Are…
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I'm comparing to the finest solid mesh. I don't trust the theoretical values to use as a reference because the formulas seem too simple - No Poisson's ratio? Is stress inside or outside? Linear or nonlinear? Where do the k factors come from? Where d…
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I'm still not seeing much problem. Where are you measuring the stresses? I checked some of them a small distance from the base, and von Mises is 0.5% error with 10,000 nodes. Axial is worse, but approximately 0 error for 39,000 nodes. Shear is the w…
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I don't really see much of an accuracy problem. I tried to recreate the model from your PDF - 6.015 m diameter and 5 mm wall thickness, clamped at the base. I didn't get anywhere near the same stress so I probably have some parameter wrong, but I di…
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You could try S8R instead of S8. I think that might perform better but I'm not sure about thin-walled structures in particular. It's now under CCX -> custom element type. The stress near the clamp presumably won't be correctly predicted by the t…
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Yes, those are limitations of it, unfortunately. It's quite a low-level tool that's not good for local refinement and the R,S,T directions depend on the element's node connectivity which aren't necessarily related to the U,V,W element orientation co…
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The procedure is similar to coupling thermal to mechanical for thermal stress. 1. Solve with DC current flow. 2. Add power density to the solution. 3. Switch to a Thermal analysis type and use Transfer internal heat generation from solution under Lo…
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Either solver would do for the thermal solve. Then yes, switch to Static 3D or any mechanical analysis type that allows thermal stress. That will have to be CCX though. Define the temperature dependent Young's modulus using CCX cards.
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While I don't know about RISA 3D specifically, there are a lot of formats Mecway can import nodes from. Here are the ones that other FEA software might be able to export: * .dxf POINTs become nodes. What settings are you concerned about? Just try…
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Thank for working out those shear components. I checked all 6 of them on an arbitrary shaped model with an arbitrary stress state by: * comparing to stress in global coordinates in the XZ plane, and they're all the same as that on at least a coup…
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You mean a way to make existing formulas available to other files? I'll try to make them work with Import but for now, you can open the .liml file with a text editor and copy and paste them between files. A formula looks like: m sqrt…
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Do you mean that it imports with File -> Import? Or that it can be used for the loads and constraints too? In the first case, probably. I think it's just my oversight that it doesn't get imported. In the second case. It seems more complicated. …
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It seems to fit more than about 60 000 characters. I don't know if it has a hard limit. It automatically wraps if the line is too long for the window.
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The only other way I can think of is *PRE-TENSION SECTION. See the CCX manual for details. It's fairly complicated to set up but it couples two nodes together and to a reference node such that if you apply a force do the reference node, it becomes t…
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Radial displacement is (x*u.x + y*u.y) / sqrt(x^2+y^2) which is the dot product of the normalized position vector and displacement. I think you can get tangential displacement with a cross product but not sure of the formula off the top of my head.…
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I don't know how but I've heard of people solving much larger models. Perhaps check on the CalculiX Yahoo! group.
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Thanks for the suggestion. It's one of those tricky things where the common use is a special case. Joining the ends would make the behavior of the tool more unpredictable even if it's more convenient most of the time. So I'm not sure really.
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Those are the units for x,y,z used in the formula. Line pressure is force per unit length instead of area. You can use either on the edge of a shell with the internal solver but only pressure with CCX.
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I've found the limit is typically around 300,000 nodes with 16 GB of RAM. I expect you would be able to go higher though. You can delete half the mesh and solve to see if it succeeds. The closest things to contact for the internal solver are: * …
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That's one of the usual ways CCX exits when the model is too big. I don't think it can use all of 64 GB of RAM unless you compile it specially. Did you see how much it did use? It might be limited to 16 or 32 GB. 900,000 nodes could easily exceed on…
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Not sure. I hope that there's another way to identify improper meshes like an exit code or error message or something. That'd be easier from my perspective.
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I don't know how changing material properties would help with allocate failure but maybe that somehow keeps it under the limit, or maybe it was by chance? There's no special rigid body without defining it through CCX cards, but you could use a very…
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One of the corners is missing. But that is weird that it silently generates the surface mesh. I didn't know that was happening.
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Node 7179 is part of the the very first bonded contact's slave surface Pipe_to_Tape as well as Pipe_Exterior_Master. So that's why it fails. An intersection between 3 parts all having bonded contacts on their common edge is limitation that you can't…
