Stuck? 
support@mecway.com
support@mecway.com
Mecway
FEA
Victor
About
- Username
- Victor
- Joined
- Visits
- 4,787
- Last Active
- Roles
- Administrator
Comments
-
Mecway doesn't have different global coordinate systems, but many features can be defined using functions of position which allows you to achieve the same effect. If you mean the element coordinate systems, you can set them all parallel to the cone…
-
It's sort of a bug when Show thickness it turned on because the thick shell faces can subtly cover the points where the nodes are. Disla. Thanks for the request. That adds to somebody else who asked for it before.
-
1. CCX can use tri3 elements for shells, but don't because they're not very accurate. Use tri6 instead (Quadratic elements in Meshing parameters). 2. The warning is normal for nonlinear analysis without the quasi-static option turned on. The error …
-
The U axis is defined like that, yes. If you make the element using New element then it's directed from the 1st node to the 2nd. The other axes only have a fixed default orientation until you specify a new one.
-
Sure. The node connectivity (changed with Invert) defines the U axis while "orientation" defines the other two axes. An easy way to make them all point out is with Loads & Constraints -> New element orientation like the attached picture.
-
The common "dumb" way to solve rigid body motion is to put weak springs on the free part. Use a line2 spring element fully constrained at its other end. Then in the solution, check the reaction forces on the spring's constraints to ensure they're ve…
-
Select some elements, then click Mesh tools -> Invert. It might be hard to see the axis lines but the red ones (U) are reversed. One of the others will be too to retain the right handed coordinate system.
-
Good to know turning on contact works! You're right that stick slope doesn't matter with TIED. Just put anything there to satisfy CCX. Sorry, stick slope does matter. That's what determines its stiffness in the sliding directions and should be as …
-
I don't think being too low should have that effect if there's nothing else wrong with the model - it should cause the linkages to spread further apart and intersect the pin. Any rigid body degrees of freedom that are only constrained by contact, o…
-
If the deformation scale factor is >>1, they might be rotating, which looks like radial expansion when it's exaggerated. In that case, you might need to attach them to something or constrain them to prevent rigid body rotation.
-
For beams, you might also want to reverse their longitudinal (U) axis, which is Mesh tools -> Invert.
-
Yep, that looks fine except GPa/m. That formula makes the elastic layer between the parts roughly 10 times stiffer than the part whose thickness you used.
-
Transfer displacements from solution should be OK. Just set the time slider to the step you want before using it.
-
I think you have to use *SURFACE BEHAVIOUR for that but I've never used it so not sure. *TIE (Called *TIE (CCX) in Mecway) is a hard connection made with MPCs, similar to the default bonded contact. PRESSURE OVERCLOSURE=TIED (called Elastic (*CONT…
-
That's gone, sorry. Some of its use cases can now be done with formulas in Loads & Constraints -> element orientation.
-
The web and flanges of the stiffener are only connected together at a few discrete points instead of continuously. This is partly because the meshes aren't compatible. You can see the gaps with View -> Open cracks. Refine most of the web elements…
-
The mesh for the stiffener has some incompatible parts where the outer edge is refined separately from the rest. I recommend deleting the whole outer row of elements because it's going to be difficult to repair. There are two ways to have multiple…
-
That's a limitation that it doesn't work when it's displaying multiple variables together, sorry. Here's an example of a formula for absolute value of longitudinal stress in MPa.
-
Version 10 will probably have max and min functions added to the formula tool so you'll be able to create a new plot that way. To set the contour plot range to fit a selected component, right click one of the selected elements and choose Fit contou…
-
Do you want to show the maximum value of normal+bending stress over the cross-section of the beam? I can't think of a way to do that, but you can at least see both sides simultaneously using any of the 4 "point #" stresses in the older version of yo…
-
They have to add up to 360 degrees or the solution will be wrong (internal solver) or fail (CCX). There is some redundancy there and in principle, it could estimate the number of segments from the mesh. But there may be ambiguous cases like the node…
-
With the internal solver, the number of output segments is only used for modal vibration. In other analysis types, the results are identical for each segment so it would mostly be cosmetic to show them. I agree that this should though, it's just mis…
-
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…
-
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…
-
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…
-
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…
-
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…
-
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 …
-
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.
-
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?
