Algor layered mesh

[4Pipes]

Does anybody have success mating layered mesh parts against say brick or plate parts? I have tried curved layered mesh against plate elements and simple dead flat layered mesh against brick parts.

Neither give clean mating surfaces on layer 15. Should they? The layered parts I have tried are constant thickness. The models have meshed and mated perfectly with all brick elements for all parts. (Other then insufficient through thickness elements).

 

[GBor]

Not sure I understand what you are trying to do, but if you are simply trying to place a duplicate mesh of say plate elements on top of bricks, mesh the bricks, then select by surface, right click on the surface and select the lines of the surface (option at the bottom of the right click menu). Then right click on the lines and select "duplicate"...it is about 7 or 8 options down the menu tree.

 

[4Pipes]

Gbor, thanks for the reply.
I am looking at a multi part structure. Say a support for a tank shell. The support is connected to the shell via the stiffeners. The wall is plate elements. I tried layer elements on the constant thickness stiffeners for to get both the though thickness elements and the geometry. The support brackets are brick. The model surface matches fine with brick and plate. That is ok apart from the lack of through thickness elements in the stiffener. I have tried extremely simple 3 part plate - layered - brick models and still cannot get surfaces to connect cleanly.
My work around is accept a loss of geomety and use plate for the stiffeners. Close enough for what I need but loses visual appeal and is a hassle.

 

[GBor]

If I am understanding correctly, the main problem is when you have 3 (or more) parts "layered" on top of each other. For me, this often requires that I manually mesh some parts, or at least the areas of "overlap". The plate automeshers will generally mesh at the mid-plane, then, the node proximity will snap the mesh together. Because an analytical gap exists between the mid-plane of the plate and the surface of an adjacent brick (equal to 1/2 the thickness of the plate), only certain nodes are considered "aligned" and will snap together. This usually makes quite a mess.

When this happens, I will often delete one of the surfaces, duplicate the aligning surface onto itself as described in my previous post, and move all of the nodes of now both surfaces to the appropriate location at the interface, but this is primarily for plate-on-plate. For plate on brick, I just duplicate the brick surface. you may have to fill in some gaps, and depending on the complexity of the problem, this may be intensive, but use the filters to isolate different layers, surfaces, etc. You can get there.

I could get on my soap box about not relying on the auto-meshers to do everything for you, but if this is the problem that you are running into, you will figure it out soon enough. There is a reason why hand-meshing still exists, and it isn't because I was created first.

GBor

 

[4Pipes]

GBor,
Thanks for the comments. I'll have a look at this.

The plate in this case was from a surface that was outside surface of the actual shell. (As opposed to a mid-plane mesh).
Plate - brick - brick = perfect and looks good - if through thickness is ignored.
Plate - Layered - Brick = will not work
Plate - Layered - Gasket - Brick = will not work

 

[GBor]

I'm pretty sure it has to do with the "sandwich" that is basically being formed. The software doesn't know what to match and what not to match.

There may be a another way: make sure that the surfaces of the matching layers are of the same size. Depending on what CAD software you are using, this can be done in different ways. Most of them offer some type of "slice" where you cut through the parts. Then, when you import them in to Algor, the boundaries, which determine the mesh size and lay-out, are identical size. Since the mesher operates the same, the mesh that it produces should come out pretty much the same. Not sure how complicated the model is, but you may want to give this a shot...it is, in large part, the difference between CAD modeling for FEA and CAD modeling for manufacturing...and these two types of modeling are different!