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Victor
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I'm pleased that it's working for you but I don't understand what caused it so if anyone else comes here with the same problem, please say so. That is an error message about ngmeshed.vol while you're opening a .liml file.
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I agree about fixing the shaft unless it's spinning so fast that dynamic effects are important. The worst case force is at the tip? I guess deformations are going to be large before it breaks and that perhaps the tip bends over, distributing the fo…
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In my 3rd option, you would mesh them separately and use bonded contact. To get the 2D section, just delete all the other surfaces of the surface mesh. Edit -> Invert selection can help here. I Sergio's idea of making a 2D STEP file with all the…
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I think both ways of meshing will be OK. #1 would get a more efficient mesh, especially at the connections because it avoids bonded contact stress error and also on the thin braze layer, because hex20 elements can tolerate a very high aspect ratio.…
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It sounds normal. but some display settings can slow it down a lot: * Tools -> Options -> Contour plot -> Resolution at either of the top two settings. * In case they're still 2D shells, not CCX's 3D solids, Show thickness. This triple…
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I think that message might just be reflecting the OMP_NUM_THREADS environment variable. When I change that, it changes the number in the message to match but I still see only 25% CPU usage on my 4-core computer when CCX says "up to 4 cpu(s)".
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Thanks for the comparisons. It's not supposed to be compiled with the multithreading option so I don't know what's happening there. It's based on the General Electric version. I heard from a former colleague of the guy who compiled it that he's qui…
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Do you currently have the same problem with version 8 here http://mecway.com/download/mecway80.msi ? If not, can you show a screenshot of when it fails?
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That behavior is intentional. The mesh made from a STEP/IGES file is linked to that file so it gets replaced when you remesh it. But any other mesh, such as made with the Mesh tools menu isn't linked to anything and doesn't get updated. It's a bit o…
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Thanks for spotting that. I found Gmsh 3.0.6 (latest stable) works OK but 3.0.7 (latest automatic) has this scaling problem, so for now I'll assume it's a bug in the non-stable Gmsh. Mecway assumes the output from Gmsh is in mm because that's how i…
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Nothing useful at the moment. Just using *BEAM SECTION instead of *BEAM GENERAL SECTION since the latter seems to be deprecated in 2.13.
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That's a good point. I'm not sure the best way to do this because the UI for Gmsh is already getting a bit complicated, but I'll try to add a checkbox or something to disable them. I think Mesh.Format = 1; should remain because 1 (msh) is explicitl…
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It's supposed to show the nearest time step that exists in the solution. It doesn't interpolate between them or anything like that so they often won't have the exact same value. With automatic time stepping, they can be spaced quite far apart. The v…
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This seems to be a limitation of CCX 2.11 which Mecway still has. You can install CCX 2.13 and it does produce stress for the BOX section shape.
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I misunderstood the type of data you have, sorry. What I said was for a time series. CCX has spectral response (*STEADY STATE DYNAMICS) but it's not supported by Mecway so you'd have to write the cards by hand and possibly use CGX for post-processin…
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Gravity is under Loads & Constraints for the Dynamic response 3D analysis type but it's not there for some other analysis types which might be why you can't see it. You can specify components in all 3 dimensions so you would add the constant rea…
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You can fix the base and apply the acceleration as a time dependent gravity to the whole structure. Paste the data into the table in the gravity load. There's no acceleration boundary condition input.
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Only one, which I think confirmed it.
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Wow, this is a fairly serious bug. Thanks a lot Johan_S, DaveStupple, and disla. It extends to some other features too. Here is the scope of what's affected: Time dependent values defined by a table for: * Temperature in thermal analysis with th…
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Perhaps you could use internal heat generation instead? That does allow a formula with position. You could extrude a thin layer of elements from the surface and apply the internal heat generation to those.
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The symmetry of a cylinder should cause modes of the same shape but different orientation. Can you identify if any of those modes are wrong (internal solver) or missing (CCX)?
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Sorry about the lost file, I don't know why. Could you email it to me? Did you set the Shift point under Analysis settings? Pick a number below the lowest buckling factor, the higher the better, but a very small value like 0.00001 should still prod…
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It sounds like that means you should make the surfaces closer to the same shape as each other, so they don't need to be deformed by *TIE. Have you looked at the elements identified in the error message to see how they might be deforming? I notice t…
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Strain and principal stress aren't available for beams with the internal solver, sorry. Only the longitudinal stresses. You could use the CCX solver which does produce general 3D stress and strain for rectangular and circular beam sections. Be sure…
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I've just worked out the matrix equations for stress transformation and it ends up quite simple. For cylindrical coordinates centered on the origin with Z as the axial direction, the radial and tangential components of stress are, expressed in Mecwa…
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It's currently only for CCX, sorry. However, for linear analysis without thermal stress, the formula for it in terms of stress and strain components is fairly simple: https://en.wikipedia.org/wiki/Strain_energy_density_function You could put it i…
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I got the formula from the dot product of the displacement with the unit radial vector. From the meaning of dot product, that gives the component of displacement parallel to the radial vector. Both your formulas look like they're for a cylindrical c…
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It's supposed to mean the element is so badly shaped that it's not really a solid anymore - eg partly inside-out. It sounds like you're near to solving it if it works for each part separately. That indicates the mesh isn't faulty. Are you using *TI…
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You could technically do it using formulas, but they'll be fairly big. You'd be expanding out two 3x3 matrix multiplications as 6 scalar equations. The formula for rotating the stress tensor is well documented, such as: http://www2.mae.ufl.edu/haf…
