How to mesh internally grooved tube in ICEM CFD?
 

Dear all,

I want to do simulation of internally grooved tube. I am using Ansys FLUENT 17.2. I have tried to make mesh by using ANSYS Meshing but it only generates tetra mesh. I want to make mesh like the attached figure by using ICEM CFD 17.2. But, I dont know how to do that. I am beginner in ICEM CFD. The hex core in the center of the tube and Pyramids, tetrahedrons and prism on the near of the wall. Is there any suggestion? Thank you

The procedure is: 1) use the Robust Octree mesher to create a tet mesh, 2) Then create prisms on the walls. And 3) finally, in Edit mesh, convert 12 tetrahedral elements to 1 hexahedral.

awkward mesh
 

Hi Gert-Jan

I am sorry for late reply. Actually, I am still studying ICEM CFD for meshing. I have tried your suggestion but my result is too poor. I don't know how to set global mesh and local mesh. In Ansys Meshing, I can do both global and local because I can define the size different shape. However, In ICEM CFD, I am confused because When I change the setting bigger or smaller value but the result is the same.

Do you have any suggestions?

Thank you

In the screenshots that you show, you should tick the third icon to open a menu where you can control the element size on the surfaces of the small objects.

fail in inflation layer
 

Dear Gert-Jan

I try local mesh by adjusting setting in surface mesh and volume mesh. I get better results. The mesh number 6391830 elements, 1078597 nodes. But, I think it's too good so the computer work heavily. Maybe I'll adjust the value. Furthermore, I can not make inflation layer near the wall. Every time i adjust the inflation option, it is failed.

Do you have any suggetion?

Thank you for your helps

If you don't show the error message, I can't help. Because it can be anything.

Btw, in general it is useless to mention your number of elements or nodes. However, given the huge number, this wil ltake a lot of time. Since you don't know what you are doing, I would strongly suggest to start with only a short piece of your pipe and try to learn the software. Learn how the refinements work and try to generate prisms.

the logic of creating a mesh in ICEM CFD
 

Dear Gert-Jan

Thank you for your suggestion. Yes, you are right. I don't know what I am doing. I have tried several tutorials about ICEM CFD which published by official Ansys or unofficial on youtube. I have found the logic of creating a mesh in ICEM CFD which is completely different from Ansys Meshing. It is interesting. Thank you for your support. I will ask you if I find any problem.

Thank you
Teguh

I like ICEM a lot since it is very forgiven w.r.t. bad CAD. It always gives me a mesh, no matter how corrup tthe CAD is.


But start simple. That is always helpful.

combine of 2 meshes
 

Dear Gert-Jan

I have simplified my geometry. I have tried several methods to mesh the tube. Most of them have failed in the inflation part. I read this thread

https://www.cfd-online.com/Forums/an...HjO6_xkgcwgoE0

I follow the step by meshing the core and near-wall mesh separately. However I found the problem with the interface of each mesh. I read some thread they said that it needs to have similar mesh/quality between interface of each mesh. But I don't succeed.

Do you have any suggestions?

Thank you for your help
Regards
Teguh

Why do you have the inner cilinder?
Isn't the problem that your obstacle is too close to the outer surface of your inner cilinder? Then ICEM can't build the inflation since there is no space......

conformal mesh solved
 

Dear Gert-Jan

Thank you for your help. I have tried in icem but it's not easy but I have found how to make conformal mesh by using ansys meshing. I share in here if there is anybody face the same problem as mine. I make my geometry in Space claim, then I edit it in Design Modeller to I unite two different body through form new part option. I follow the step in this link (https://www.youtube.com/watch?v=N-eOwfYiysE) Then, make a mesh in Ansys Meshing. It works.

Thank you
Best regards