error in COMSOL:'ERROR:6164 Duplicate Variable'
 

Hello,

I am working on a model which has 'level set 2 phase flow --> chemical engineering module' and 'Axial symmetry, stress-strain with fluid interaction --> fluid structure interaction --> structural mechanics module'. basically i have a model in which there are 2 fluids of different density and low density fluid is at bottom initially. as it moves up, it will exert force on a flexible cantilever beam attached in midway. i am finding the effect on that beam including displacement and stresses. i am having following error 'ERROR : 6164' and following detail message. ***********************************************

Exception:

com.femlab.jni.FlNativeException: Duplicate variable name Messages:

Duplicate variable name

- Variable: r

- Variable: rTIME

- Variable: z

- Variable: zTIME

- Variable: r

- Variable: rTIME

- Variable: z

- Variable: zTIME

- Variable: r

- Variable: rTIME

- Variable: rr2

- Variable: rz2

- Variable: z

- Variable: zTIME

- Variable: zr2

- Variable: zz2

Stack trace:

at xmodel.cpp, row 840, ()

at com.femlab.xmesh.Xmesh.meshExtend(Native Method)

at com.femlab.xmesh.Xmesh.meshExtend(Unknown Source)

at com.femlab.xmesh.MeshExtendRunnable.run(Unknown Source)

at com.femlab.server.FlRunner.run(Unknown Source)

at com.femlab.util.ad.run(Unknown Source)

can anyone please show me what can i do in this situation?

Re: error in COMSOL:'ERROR:6164 Duplicate Variable
 

Hi,

The explanation of this error message in the Diagnostics section of the COMSOL documentation says:

A variable name has two different definitions. For instance, the same variable name appears two or more times for a dependent variable, a constant, an expression variable, or a coupling variable. Remove or rename one of the variables.

In your case, you are combining two in themselves rather advanced interfaces: the level-set two-phase flow interface and an FSI coupled multiphysics interface. The FSI coupling includes an ALE application mode that provides a moving mesh, so there are two different "frames" in the model, as well as two different application modes for the fluid flow.

It might be a good idea to first solve a simpler case and then add more physics incrementally.

You can also contact the COMSOL support staff at www.comsol.com/support or support@comsol.com

Hope this helps,

Magnus Ringh COMSOL