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Victor
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Comments
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The internal solver can be very slow when there are lots of constraints. If you can use CCX instead, that would be faster. Sergio - the inefficient writing of some BCs is a tradeoff in complexity of Mecway's code vs complexity of the resulting .inp…
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I don't see that you need the at-origin beam or the constraint equation coupling it since the 3 sensor beams on the plate also show the same 90 degree rotation. I would also use a soft material for those beams to ensure they don't artificially stiff…
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This dot product stuff is for measuring rotation in the solution, not prescribing it. It doesn't let you specify the displacement amount as a formula in terms of position. Do you really want to leave them free to move radially and axially as oppose…
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Yea, Mecway can't calculate the center of rotation. Sorry if it looked like I was explaining basic maths. I wrote out those formulas in Mecway's formula format so you can copy and paste them in to get a feel for its capabilities with minimum frustr…
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Yes, the formula gets calculated for each node and can be a function of that node's displacement and position. I don't completely understand what you mean by the center of rotation being displaced. If you know the center of rotation then you can us…
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The display shows the midplane in the same place the solver will see it, So being offset like this can have a significant effect bending moments, depending on how it's loaded. Since the mesher can't find the midplane, you could either move the CAD …
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I see. Yes, that would save you redefining components every time. I don't have any more suggestions, sorry. You can reverse shell elements with Mesh tools -> Invert, though it will be lost when you remesh it.
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I use Gmsh 2.16 and 3.06. Some STEP files make it crash doing a volume mesh but others are OK and surface mesh is more often OK. I'm not sure why. How does different thicknesses prevent you merging them in CAD?
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Some options: * Merge the parts in CAD in advance. * Use bonded contact to join them. * Try Gmsh which seems to be more consistent at keeping same-shaped faces having the same mesh.
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1. Yes, rotation constraints won't work on solids, and yes, you could use bonded contact to join a beam to a solid then use its rotational DOF with the internal solver. However, it doesn't look like a rotation constraint is appropriate here. The gea…
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The reason for specifying shell/membrane is just an organizational thing to enable the thickness parameter and disable all the irrelevant beam parameters/etc. The CCX solver expands shell elements to solids so it's not really using a shell formulat…
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The cutting plane slider (see attached picture) hides foreground parts. If the assembly has different components, it can be easier to hide a component instead. Right click its name in the outline tree and then Hide. Bonded contact isn't automatica…
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A point that might be confusing is that "orientation" here doesn't affect the shape of the mesh, just the direction that the composite material is aligned with. So disla's (0,z,-y) formulas would make the U axis in the circumferential direction des…
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Hello Eduart 1. Yes, I think quad8 (quadratic, quad dominant) is best. Quad4 may be OK too. Yes, turn on Fit midside nodes to geometry. That's only off because it sometimes makes badly shaped elements which won't solve. 2. Yes 3. The default elem…
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Some file types are not allowed so you can zip or rename them. Or sometimes the forum is just flaky and refreshing the page might help.
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Every point behaves as if it's undergoing a temperature change from the reference temperature to the temperature that you specify for it, ie. ∆T = T - Tref. Internally, it calculates that ∆T, discards the other two temperatures, and uses a generaliz…
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If the ends are fixed in the horizontal direction, then yes, nonlinear should have less deflection because the sheet would be stiffened by its tension, similar to a catenary. If one end is free to slide horizontally, then I'm not so sure but I woul…
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The box that's initially stationary has 3 unconstrained degrees of freedom making it free to slide around however it wants in the XZ plane. It requires 0 force to do that, so it can easily be moved by anything. Adding a floor object with friction s…
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It's a strange one that I can't solve, sorry. Gmsh (option in Meshing parameters) works OK though. Here's a solid mesh I got. If you don't want to install Gmsh, another way is to export as an stl file and mesh it in Mecway with Mesh tools -> Aut…
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Not sure if/when I'd add it sorry. Here's a document written by Anthony Falzone which contains the maths. I don't understand it but it seems to work perfectly*. The key equation is: α = -2 Ω ω where Ω and ω are two angular velocities about two pe…
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Those temperatures don't sound right. Won't they have a artificial thermal contraction in all the non-brazed regions, followed by an even worse one in all the non-weld regions? I think if you use a 0°C reference temperature, you can set the brazed …
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Sometimes a single large complex surface can cause problems. Maybe the conical(?) surface with the holes is like that. If you can split it into several, that might help. You can try turning on Tools -> Labs -> Smooth geometry preview (slower)…
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Angular acceleration is just not implemented, sorry. There's no major reason other than that not many people have asked for it. The reason centrifugal force and linear acceleration are available in Quasi-static analysis is because they're putting t…
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It doesn't currently have either of those features, sorry. You can generate a model with your own software writing an XML .liml file and running Mecway with the command line parameters to solve it. It can also output solution data to a .csv file (So…
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Changing x to radial can be done simply by changing the direction vector from (1,0,0) to the radial direction (x,0,z). Also, just for convenience, it's not necessary to include so many data points in the table since it gets linearly interpolated any…
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I think all those steps up to before the welding are doable through the UI. The only risk I see is if the flange has to push the ring through a large strain with a corner-to-surface contact, it might fail. A few people have had trouble with that sit…
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This is a type of problem that has come up a few times and there's sometimes no good way to do it with Mecway/CCX because of the key point you said about stress being lost after solving. You can get around that by running one big quasi-static solve …
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1. The edge of a quadratic element is always a parabola or a straight line. To make multiple elements fit that curve, you could use the curve generator or start with a single non-straight element and refine it multiple times which preserves the quad…
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This seems to be a bug or at least a missing feature that lacks an error message. Loads aren't allowed on the 1D faces of line3 elements with CCX. It looks like force is the only load that meets those conditions. Thanks for pointing it out because I…
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I used an old example that doesn't quite match your case, sorry. Just change the (-y,x,0) to (x,y,0) in the first displacement constraint in the example to change it to radial. To contract it instead of expanding it, use negative coordinates or a ne…
