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Victor
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Comments
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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…
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It's actually in the right-click menu of the Solution branch of the outline tree. That's a mistake in the manual so thanks for pointing it out.
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Though Sergio's idea is probably easiest, an alternative which works with either solver is to create a New formula under Solution to convert reaction forces into moments, then use Tools -> Sum to sum them over the constrained nodes. Here's an exa…
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Hello 28kevinf and Welcome to Mecway **1) The displacement for the first few modes shows rigid body rotation which looks like radial expansion/contraction with the large automatic deformation scaling factor. To prevent these modes appearing, constr…
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WARNING for anyone else using this. SandpointDave discovered that the SECTION FORCES results are wrong. This seems to be a bug in CCX 2.10-2.13 for circular tubes. It looks like you can do further calculation on the results to correct for that thoug…
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I see. I misread your 37000 as the total number of nodes. I've reproduced it with your model. This appears to be caused by memory fragmentation and I've now fixed it for the next version so thanks for bringing it up. It's the combination of a large…
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There's no hard limit and I'm surprised it failed with such a small model. I'm having trouble replicating your results. I tried with both fixed support and frictionless support on 36 000 nodes of a 116 000 node model (attached) and it used about 1-…
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This is probably because two or more bonded contacts are sharing slave nodes where all 3 parts meet. It's a common problem without a simple solution. Some suggestions: A) Make a small chamfer on those edges so there are no common nodes. B ) Manual…
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There's a tutorial on frictionless contact in the manual called PipeClip.liml For friction, you set it up the same way but add a friction coefficient and stick slope. Stick slope is another parameter you usually have to choose by trial and error. …
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Oh yes, that looks like a bug showing the wrong error message sorry. You can just ignore it since it'll go away.
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Thanks for pointing this out. It's sort of a bug. The beam rotation in the display is done using the Twist angle field variable instead of the 3 rotation components. However, Twist angle is no longer generated automatically in version 8 so it doesn'…
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That probably means you're using shell edges as master faces which isn't allowed, but they can be slaves. So where an edge meets another surface perpendicularly, set the edge as slave and the 2D surface as master. If that's not your intention, mayb…
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You can use the SECTION FORCES parameter on the *EL FILE card. To do this in Mecway, under CCX in the outline tree, add a custom step contents containing: *EL FILE,OUTPUT=2D,SECTION FORCES S Then the stress components in the solution have differen…
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The main problem is that the two SSteel materials have Youngs modulus = 200 Pa. I changed them to 200 GPa and it converges. I also turned off quasi-static since there aren't any time dependent loads to make use of it.
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3-point bending with contact is a bit difficult because the bar and the loading cylinder can fly away if they're not constrained. But you can do it with both the free objects having all 6 of their degrees of freedom each constrained by soft springs …
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I forgot about this, but you can use normal pressure and enter a formula to make it a linear function of position. That's the same as hydrostatic pressure when the edge of the selected faces is along the free surface.
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I might add it for linear analysis by exporting it as node forces. It won't work for non-linear though because they won't follow the moving mesh, and from what I can tell, CCX doesn't support non-uniform pressure loads without writing a user subrout…
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Yes, all configurations get all of them unsuppressed at first.
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I see the convenience of having analysis type settable per configuration but I don't expect to make that change. If you have several configurations with different thermal solutions, you can still transfer all their temperature fields into static co…
