Matching three flat plates with multizone mesh
 

Hello everyone!

I've been reading on this forum for a few months but this time I wasn't able to find an answer...
I am working on my master thesis. It's a waterjacket for a woodchip fired boiler. I am not allowed to show you screenshots of the geometry.

The large and thing plates are part of the waterjacket. The plates are about 25-30mm thick, 1200mm high and somewhere between 700 and 1200mm long (50"x40"x1" or so). The plates stand together in an U-shape (one horizontal, two vertical) and have several cutouts where I had to do Tet meshing. The three plates are three separate bodies but form one part, later on they are a fluid zone.

For Fluent analysis, I want to add a Hex mesh for the large parts. Mesh quality is really amazing if I only add the hex mesh to one of the three plates and supress the other two. But if I want to add the hex mesh to all three plates the mesh does match at the interfaces but has
a) a really bad quality if I allow some Tets in the Multizone mesh or
b) Ansys Meshing just gives me an error

The error message says something about manual sources for the mesh even though I have set it to automatic. Sorry that I can't post the whole error message, I am Austrian so I have a german version of Workbench and all my errors are german... probably bad for posting in an english forum.

I hope you can understand my problem and could give a good advice, please.

Thank you!

With the interface problem if you want the mesh of the three bodies to be joined you need to select the three bodies in design modeler and form one part from them. this is not the same as doing a boolean operation. When you form one part you will still have three bodies but the meshing will be conformal.

Also, with the automatic source and target. It is only easy for the software if the two ends of the part have the same size to understand how to do an automatic source and target. if it is not the same then you have to manually select it to make it easier for the software to understand. hope this helps.

Also the error messages will be the same so you can use google translate to post the message in English so people can understand the problem better if what i said above doesn't help. Also personally i think if you posted a picture from design modeler of a simple geometry with a few plates noone will patent your drawing, if you know what i mean.

Thank you for your reply. I have formed one part from the bodies in DM. I see that my problem is not quite easy to understand.

But I think the cutouts on the plates are the real problem. Let me give you an example:
You want to mesh a large, rectangular plate. Let's say the dimensions are 1000x1000x30mm (or 40x40x1 1/4"), something like that. In the middle there is a rectangular "cutout" that is only half the thickness and 250x250mm (or 10x10 inches). If you want to do this with multizone mesh where only hex cells are allowed you have to slice the plate into two parts. Am I right?

I will speak with my supervisor, I hope he allows me to post at least some pictures of the project.

You have seen the geometry I haven't, so i cant understand what a cut out is.