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Victor
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I saw your post on CCX forum so just to clarify in case of misunderstanding, it works for both static and modal with elastic support, not elastic bonded contact. In case that's no good, another workaround is to extrude a thin layer at either the sl…
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Add a formula to the solution of ( z*u.z + x*u.x ) / sqrt(z^2+x^2) I've attached an updated copy of your model that includes this.
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I'm confused about the purpose of the constraint equations and springs. Does putting the Z displacement directly on the end node of the beam lose something important?
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Thanks for posting that. I guess this shows a need for a proper distributed surface mass. What does that mass represent?
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Oh, that's funny. It works if you have stress stiffening but not without. It seems like it requires the static *STEP that comes with stress stiffening and then remains active for the subsequent *FREQUENCY step.
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Yes, it's having constraints on the slave nodes of the bonded contact. A workaround it to replace the frictionless supports with elastic supports with eg. 1e15 Pa/m Normal stiffness per area and 0 Tangential stiffness per area. I don't know why el…
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Not currently available sorry.
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Yea, you can't set stiffness too high compared to the rest of the model or it won't converge but as long as it does, it should be OK. 1e15 Pa/m isn't very extreme for a meter-scale model compared to steel having E ~ 1e11 Pa. Automatic bonding is on…
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Thanks for solving that. Modal mass/etc is on my list as a few people have asked for it before but it probably won't be done for the next version, sorry.
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As JohnM says, there isn't a simple reliable way to identify them. CCX's output of contact stresses is only on slave nodes, so you can't use that to spot zero-stress nodes. It's WarnNodeMissTiedContact.nam output file showing missed contact nodes is…
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The CCX manual theory section (6.9.2 Frequency analysis) says the units for effective modal mass are mass*length^2 and from the formula for total effective mass, it looks like that also has the same units. I don't know what that means physically. T…
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Version 13 has a mecway.exe.config installed with it. A difference is that it now requires .Net Framework 4.5 and probably no longer works with .Net Framework 3.5 because it includes IronPython which has that dependency. A minimal version of the fi…
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Good spotting. I wonder if there's a way to rewrite it without the singularity?
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Right click the slider and choose Max/min... where you can type in the two limits.
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Yes, apply them to surfaces in the Geometry view for them to be retained. When creating the loads, right click the geometry surface (or ctrl+click first for multiple surfaces), and choose Loads & Constraints -> .... To change your existing l…
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If the surface meshes on the interfaces are the same, you can combine them in Mecway with Mesh tools -> Merge nearby nodes, but if they're not, you can't. Bonded contact may be an option if you can't get the meshes to match.
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I see it can also export I-DEAS .unv format which Mecway can import, so you could try that.
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You can use Solution -> New formula to do the multiplication and that creates a new solution variable containing the result. If you do need to read solution variables back in, probably the easiest way is using the Gmsh .msh format which is fairl…
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No, sorry. Other than zero the offset for all elements then undo or open a saved copy to reinstate them.
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I'm a bit late to the party, but I notice your first picture shows the external force is being summed on Optic_underside. Is that the side in contact with the o-ring and without the load? If so, it won't work because contact forces aren't included i…
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No worries. In earlier versions when the sample was made, all the solution variables were included automatically, but most of them are now optional.
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You mean heat flux? Add it through the menu Solution -> New thermal and fluid -> Heat flux.
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No way to keep edge loads, sorry. Another possibility is to use 3D solids but with a smaller segment size, such as 1 degree so that the solving is fast. Put frictionless support on both symmetry surface to enforce the axial symmetry boundary condit…
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You can do a Surface mesh (in Meshing parameters) then delete all the surfaces except what's in the XY plane for axisymmetry.
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Tension-only is a nonlinear effect so it can't be used with linear buckling. However, if you know whether each one is in tension or compression then they're equivalent to ordinary spring/truss elements or nothings respectively. But that's only line…
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Hopefully in a couple of months.
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I agree with rwhirley. If the goal is to verify the design, then the actual stress concentrations that it has would be important. If the goal is to verify that Roark's agrees with the idealized theory it's supposed to agree with then you might have …
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If it really is a stress singularity, then I'd be skeptical of the meaning of the stress given in Roark's since that doesn't make sense on the face of it. Could it be that Roark's just neglects the stress due to the stress concentration in the same …
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It's connected by bonded contact in the 2nd configuration.
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It looks like you're nearly there. Use a smaller time steps size to sample and simulate the excitation frequency properly though. I'm not quite sure what your question is. Do you want to adjust the stiffness by changing the geometry of the secondar…
