Hi Soheyl,
There are two possible workarounds for this problem.
The first (and simpler) assumes that
a) You are using version 5.0
b) The deformations are so small that that the geometry of the fluid domain does not change.
In this case you can switch to the new 'Fluid-Structure Interaction, Fixed Geometry' instead of the more general 'Fluid-Structure Interaction'.
The second (and more general) workaround:
1. Add an extra Solid Mechanics interface to your model.
2. Change the name of the dependent variable in the Solid Mechanics interface so that it matches the name in the FSI interface. Typically: Replace 'u' by 'u_solid'. This is done in the 'Dependent Variables' section of the Solid Mechanics interface.
3. In the Solid Mechanics interface, select only the viscoelastic domains. Assign a viscoelastic material to all domains, and copy the viscoelastic data from the FSI interface.
4. In the FSI interface, replace the material for the viscoelastic domains by a Linear Elastic material with very low stiffness.
In effect, this approach will give you an overlay of two materials (one elastic from FSI and one viscoelastic from Solid Mechanics) for each viscoelastic domain. As long as the elastic material has a low enough stiffness, it will however not affect the results. Since there is no longer a viscoelastic material in the FSI interface, the variable name conflict is removed.
Regards,
Henrik
There are two possible workarounds for this problem.
The first (and simpler) assumes that
a) You are using version 5.0
b) The deformations are so small that that the geometry of the fluid domain does not change.
In this case you can switch to the new 'Fluid-Structure Interaction, Fixed Geometry' instead of the more general 'Fluid-Structure Interaction'.
The second (and more general) workaround:
1. Add an extra Solid Mechanics interface to your model.
2. Change the name of the dependent variable in the Solid Mechanics interface so that it matches the name in the FSI interface. Typically: Replace 'u' by 'u_solid'. This is done in the 'Dependent Variables' section of the Solid Mechanics interface.
3. In the Solid Mechanics interface, select only the viscoelastic domains. Assign a viscoelastic material to all domains, and copy the viscoelastic data from the FSI interface.
4. In the FSI interface, replace the material for the viscoelastic domains by a Linear Elastic material with very low stiffness.
In effect, this approach will give you an overlay of two materials (one elastic from FSI and one viscoelastic from Solid Mechanics) for each viscoelastic domain. As long as the elastic material has a low enough stiffness, it will however not affect the results. Since there is no longer a viscoelastic material in the FSI interface, the variable name conflict is removed.
Regards,
Henrik
