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Tom April 12, 2007 18:19

Defining Regions in ICEM
Hi, I am new to ICEM and I am unsure of how to name surfaces on a grid to be exported to CFX 10.0 pre for defining BC's.

I would like to open cfx5pre with my grid, click on a region (or surface) to define my bc conditions. The problem is that when my grid is loaded I cannot see any of my surfaces.

How to I define them in ICEM so that they will be exported to cfx5pre?

I am exporting using the solver: ANSYS CFX.

thanks for your help.

Joe April 13, 2007 06:19

Re: Defining Regions in ICEM
This is covered in the first few icem tuts.

myron April 13, 2007 09:06

Re: Defining Regions in ICEM
Best bet is to divide your surfaces into Parts based on the desired boundary conditions - inlet, outlet, symmetry, wall, etc. Then these boundary names will persist to the surface mesh elements and to CFX-Pre.

empirer2002 April 16, 2007 03:17

Re: Defining Regions in ICEM
Your problem is similar to my case The problem of my case is I import mesh from Tecplot files in ICEM CFD. After exporting my model to filetype CFX4(*.geo) and read by CFX 5.7.1, it's become a whole mesh and I can't indicate the position of the inlet or outlet condition.

Others told me I should build a part "surface" to indicate the position of inlet or outlet in ICEM CFD.

But after importing mesh from Tecplot in ICEM CFD, I just got a whole mesh and I can't edit it. Since I build surfaces to indicate where the position of "inlet" or "outlet", it didn't work.

Please, I need someone to tell me how to solve this question.

empirer2002 April 16, 2007 21:18

Re: Defining Regions in ICEM
Maybe another point, If I have no points, surface, and any "parts" in ICEM, I have only a mesh. How do I define properties of "inlet" or "outlet" regions in this mesh.

Dr. Flow Squad April 17, 2007 01:16

Re: Defining Regions in ICEM
Hi. My guess is that you both need som basic knowledge of the program. check out the online ICEM CFD demos on Check out "Helicopter" at the last page since it is the least advanced of the tutorials. I hope you will succeed.

myron April 17, 2007 08:37

Re: Defining Regions in ICEM
You have to have surface mesh to define the boundary conditions. If you only have volume mesh (3D elements) you need to obtain the surface elements - then separate those into the appropriate parts. Use Edit Mesh > Check Mesh > Uncovered Faces to extract the surface mesh. Then you'll have to create parts and add the surface elements to the parts of interest. See the tutorials or on-line demos for more info (as already indicated).

Patrick April 19, 2007 04:49

Re: Defining Regions in ICEM
In Ansys CFX 11.0 Pre you can rename and define new surfaces of a mesh. But it is still better to do it via parts in ICEM.

empirer2002 April 22, 2007 13:53

Re: Defining Regions in ICEM
After import mesh from Tecplot I can show the subset, vertices, and edges of this mesh, but there is no parts and geometry.

I try to use edit mesh, but I can't use the function "Check Mesh" and "Uncovered Face".

I think I lost one important step to get this function. This problem still bothers me a lot.

empirer2002 April 22, 2007 23:22

Re: Defining Regions in ICEM
I try the example "cylinder" of the Tecplot and write cylinder.dat. After importing mesh from Tecplot , cylindr.dat, the message tell me there's no toplogy do you want to recompute it. I clicked "recompute" and got no part, the "check mesh" in "edit mesh" can't be used. I still have no answers to this problem.

empirer2002 April 25, 2007 00:31

Re: Defining Regions in ICEM
Thank you for keeping answers my questions.

Your passion keeps me trying and finding ways to solve this problem.

Now, I solve this problem by another way.I'm glad to share it with you and receive your advice about my operation.

1.After importing points and building line, surface

2.Meshâ†'surface meshingâ†'mesh check 3."Volume Meshing" to build volume

4.Mesh check

5.Export fileType as "Icem CFX"

6.Import mesh(.cfx5) from CFX

then I can read the mesh I build. This is a simple flow process. I'll be glad to help with your questions.

A good day to you!

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