CFD Online Discussion Forums

CFD Online Discussion Forums (
-   CFX (
-   -   ICEM BC to FLUENT (

Simon September 9, 2008 09:36


I have searched this forum and found the post about requiring LINE elements in order to have FLUENT recognize the BC created in ICEM. However, I still do not understand how one outputs an ICEM 11.1 mesh, with its boundary conditions, for FLUENT v6.3.

I can successfully output the mesh from ICEM to FLUENT. My problem lies with defining the boundary conditions (BC) in ICEM so that they are recognized by FLUENT. I have tried setting the BC in the ICEM Output BC window, but that does not work.

Can someone please provide me with a simple procedure? This task for a 2D quad mesh.

myron September 9, 2008 14:45

Make sure the curves bounding the 2D surface are placed into appropriate 'Parts' so you can specify boundary conditions on those 'Parts'. When you create the mesh - those bounding curves should translate to LINE elements in the appropriate parts. So if you don't have LINE (1D) elements separated into your desired BC groups (Parts) - that is the problem.

Simon September 9, 2008 15:43


Thank you. I hear what you are saying, it is similar to the other post that I saw. However, I am not sure that I understand how to implement your explanation.

Let us imagine that I have a very simple geometry, a rectangular box from creating four curves from four points. The four curves are used to create a surface. I create part INLET using the left curve, part OUTLET using the right curve, part WALL using the top curve, and part SYM using the bottom curve. I use autoblock to mesh the surface.

If I understand you correctly, I need to return to my parts (INLET, OUTLET, WALL, and SYM) and associate them with the corresponding line elements if I want those parts to be BC's in FLUENT. Is that correct?

If the above is correct, would I turn off all geometry, turn on the mesh, and add the necessary line elements? Am I creating the line elements?

Thank you.

Simon September 9, 2008 17:08

Okay, this issue has been resolved. The process is indeed as I wrote above, after being prompted by Myron.

After the mesh was created and I had a good mesh quality. I turned off all geometry, leaving MESH enabled. I then added the appropriate LINES to my respective PARTS (e.g., inlet). I used the selection box, which made it very easy. I then returned to the OUTPUT tab to specify the BCs and write the .msh file. When I had FLUENT read the .msh file, all of my BC's were there.

I took the time to write what I did in hopes of helping the next person who is coming from another CFD software tandem to ICEM/FLUENT.


All times are GMT -4. The time now is 19:06.