Thanks @Fatmac. It looks like the accuracy parameter fixes it. I get a reliable 88.88 1st mode with 1e-5 whether requesting 1 mode or 3. This is with the MKL solver and no Pastix but I did see a difference without setting accuracy (89.01 and 88.88).…
You're right that it shouldn't do that. Some ideas:
Are you using the CCX binary that comes with Mecway or another one? The Mecway one has automatic shift point searching and most others don't. It shouldn't make much different here though because b…
I agree and intend to include compression-only 2-node elements in a future version. Probably with a spring stiffness (k) rather than E and A the way tension-only currently is.
If this is CCX, then Mecway only uses nodal values. It doesn't currently import integration point values from the CCX solution. Including integration point values wouldn't be trivial since it doesn't currently have any way to store or display them, …
The renumbering of non-sequential nodes is a bit complicated, sorry. When Mecway reads a .inp file, it creates dummy nodes to fill the numbering gaps, then deletes them in reverse numerical order. Deleting a node means replacing it with the node of …
Here's one approach using spring elements for the wire and pre-tension section. You have to define the preload as a length adjustment rather than a force so you'd need to look at the axial force in the solution and modify the pre-tension section to …
To be clear, this is only a problem if you're going to do mode superposition or otherwise using the mode participation factors from the CCX output files, not for general frequency analysis, is that right?
I'm not sure using the higher stress at material boundaries is the right way. While it might be practical and conservative, it wouldn't be obvious that it's doing that and there's ambiguity about how to order tensors.
I'm not sure what you mean in …
Yes, since version 25, in part because you pointed out the need. Sorry it slipped by.
The Y-rotation constraint is for the reference node (ROT node), but structure itself is free to rotate about the line of nodes because there's no way for a rigid …
You can use Node-surface coupling for this with either the internal or CCX solver, and small or large displacements. Here's an example. Note that the line axis (Y) rotation constraint is required when the nodes are collinear and it isn't actually co…
Just a thought, but perhaps it's possible to model the bolt in it's relaxed shorter state, then let the contact pull it to fit? You might have to write the contact cards by hand or disable the ADJUST parameter on *CONTACT PAIR. As with cooling, you …
Part of the difference between *TIE and unilateral may be the contact stiffness which is effectively infinite for *TIE and looks a bit low for elastic in your screenshot. I would compare bonded elastic to unilateral elastic to make it more apples-to…
I think it kind of does but the build from OpenRadioss don't have it enabled. In 2022, one of the maintainers said "It is not possible to provide the direct usage of /EIG functionality in OpenRadioss, yet." The only ARPACK alternative I know of is F…
@JohnM Amazing. Thanks. It was @Sergio who prompted me to do this. At first I thought it might be a less buggy alternative to CCX but this explicit dynamics thing is incredible. More integration coming in Mecway 27.
Not really. Here are some possibilities:
Use line3 elements and take the force at the midside node. It's still not listed under Element values but isn't polluted by values from other elements sharing the node. Beware that line3 truss elements shoul…
Oh, that's not right. It seems to be missing the external forces on one side of the shells. Here's a simplified model. I'm still working on isolating when it happens.
That's good. I still have trouble with those settings so if you do too, other things that help are:
- Smooth the corners of the curve by adding more points near whatever stress/strain it stops at.
- If the solution stops near final point (0.15, 470…
Two things:
Z Displacement constraint on the common node to constraint rigid body rotation.
Either turn off quasi-static or make the force time-dependent (250*t). Quasi-static with no time dependence often fails.
Mecway 26 requires .Net Framework 4.8 so please install that. I'm not sure why the error message says 4.0.
Mecway 23 used .Net Framework 4.5 so if it still doesn't work, maybe try that ( https://mecway.com/download/oldversions/mecway230.msi ) to se…
@LHartley only if there's no global buckling mode with a lower critical load. If you removed the guy wires, I imagine this truss/frame would begin to buckle globally before any individual member fails.
I see these error messages start to look useless when they say something's not allowed but it still works. Maybe it should explain the reasons too. Nonetheless, I still wouldn't use *TIE on shells because you never know if it's quietly over-stiffeni…
@disla
> I'm obtaining a different result each time I press the run button and only after 5-10 runs a credible result pup up which by the way only fits my expected result if I keep the second buckling factor.
Would you be able to send me that …