Consider the following two sets of boundary conditions defined in sif file for FSI problem:

1-

Code: Select all

```
! Internal FSI (Beam) Boundary
Boundary Condition 3
Target Boundaries = 17
Velocity 1 = 0.0
Velocity 2 = 0.0
FSI BC = True
Calculate Fluidic Force = True
Mesh Update 1 = Equals Displacement 1
Mesh Update 2 = Equals Displacement 2
End
! Internal Fixed Boundary
Boundary Condition 6
Target Boundaries = 20
Velocity 1 = 0.0
Velocity 2 = 0.0
Displacement 1 = 0.0
Displacement 2 = 0.0
Calculate Fluidic Force = True
Mesh Update 1 = 0.0
Mesh Update 2 = 0.0
End
```

Code: Select all

```
! Internal FSI (Beam) Boundary
Boundary Condition 3
Target Boundaries = 17
Velocity 1 = 0.0
Velocity 2 = 0.0
FSI BC = True
Mesh Update 1 = Equals Displacement 1
Mesh Update 2 = Equals Displacement 2
End
! Internal Fixed Boundary
Boundary Condition 6
Target Boundaries = 20
Velocity 1 = 0.0
Velocity 2 = 0.0
Displacement 1 = 0.0
Displacement 2 = 0.0
Mesh Update 1 = 0.0
Mesh Update 2 = 0.0
End
! Fluidic Force Calculation Boundary
Boundary Condition 7
Target Boundaries = 17 20
Calculate Fluidic Force = True
End
```

Of course it’s not a problem or bug. Maybe you were aware of it or set it intentionally this way. Anyway, it is something that I have experienced with Elmer and I here feedback it.

Regards, Hamed