Plate Mesh Inner Radius

kennethfugate

Is there a reason why the inner radius input is disabled in the plate mesh input dialog for circle, concentric circle and octogon? Using v14.0.

Victor

Inner radius is for the central hole and those shapes don't have a hole. You can make a hole by using Mesh tools -> Hole on the central node afterwards.

Plate mesh is a legacy feature that I've maintained mainly to not lose functionality, but haven't really enhanced it. Not sure there's a lot of value in having an arbitrary library of hardcoded shapes unless it can have an easily knowable scope.

Sergio

Now that the program has the preload boundary condition, maybe a new "hexagonal plate with circular pattern at the middle with no triangles at all" and "hexagonal plate with circular hole" could be usefull to build precise bolts and nuts with hexa elements. What about adding a basic profile generator for I/U/T/L/Rectangular shapes? Again could be extruded to work with solid elements.

kennethfugate

I had already used the hole function as a second step. The inner radius would be useful for bushings.

You can use it for the curved part of lugs when selecting two quadrants. You can use the square with hole with the other two quadrants to complete a lug. If the inner/outer radii and the radial divisions match, the nodes at the interface should match and merging should have no problem.

You would have more control over the number of radial divisions if it was one step in the plate generation function for circles. When doing the plate then hole process, you don't know exactly how many divisions are going to remain after the hole process.

JohnM

@kennethfugate

Try creating your plate mesh with OD that equals the inside of your bushing. Extrude this face in the axis direction by the length of the bushing, then extrude the radial surface outward normal by the thickness of your bushing. Right click the highlighted blue to identify as a different element type, then delete the inside stuff. Use all 4 quadrants so that radial mesh is outward at edge. You can delete to make half later if necessary.



You might also consider keeping a library of these parts. We do this with lots of things, but bolts, bushings, and standard "stuff" you use are good candidates. The nice thing about using a model library is that you can also pre-assign things like contact surfaces, pre-tension in these models, and they come in along with the mesh when you import.

kennethfugate

Thanks John. I don't have any issues making models. I'm just lazy and would rather not do extra steps in the creation of the geometry. I did an interference fit bushing with 0.003 inch interference in a lug model last week.

There are numerous ways to do something like a lug.
1. Plate concentric circle in 2 quadrants. Select center and use hole feature. Create other two quadrants using plate square with inner radius. Use radial divisions so the nodes on the edge match. Merge nodes on the interface. Extrude to 3D.

2. Create plate square with inner diameter on two quadrants. Select and revolve edge normal to plate around center to get curved portion of lug. Merge nodes as required. Extrude to 3D.

3. Curve circle, half circle and lines with 1D elements. Automesh 2D. Extrude to 3D. Note: this does not give a nice uniform pattern of elements.

4. Numerous other methods...

I've only been using Mecway for a few weeks now and am still learning some of the finer details of the commands and interface. I still use PrePoMax in conjunction with Mecway because PrePoMax has some features that are not in the Mecway interface. I also prefer the use of steps rather than lumping everything into one step by default. I was an Abaqus user in my previous job and am used to breaking the analysis into steps. I know I can do it in Mecway by manually adding the steps but would rather have the user interface handle it.

Victor

@Sergio, I feel that having a lot of specific pre-defined shapes could become a bit of an anti-feature if it gets big enough that it's hard to know if it contains what you want or not. The existing plate meshes are actually generated by a general purpose mapped mesher that's given hard-coded geometry definitions. Sadly, it lacks any interface to specify your own input. Ultimately, I want to fully exploit this mapped mesher with user-definable shapes and parameterized mesh densities and dimensions so you could add bolt shapes, beam profiles, inner radius or whatever.

@kennethfugate, I agree there are lot of ways to make structured meshes but nothing really convenient.

Steps are tricky because the whole application was designed around not having them. I might have to hack in some step capabilities though.