Fixed boundariesΒΆ

Learning targets

  • Specify boundary identifiers

In many typical simulation setups fixed physical boundary conditions on one or several boundaries of the computational domain have to be specified. This can be done by attributing an integer number as boundary identifier in the layout and by attributing physical properties to the corresponding boundary in the file boundary_conditions.jcm (see also description in the JCMsuite Parameter Reference).

This geometry example specifies a square-shaped computational domain with boundary identifier 1 at the left and right side of the computational domain and boundary identifier 2 at the upper and lower side of the computational domain. Note that boundary identifiers specified for the computational domain (characterized through the priority flag, Priority = -1) are attributed also at the parts of boundary segments where other objects are overlapping (here: where the tilted rectangle intersects with the computational domain boundary). The resulting geometry and mesh correspond to the following figure:

_images/snapshot_150.png

.jcm Input File

  • layout.jcm [ASCII]

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    Layout2D {
  Name = "TutorialExample2D"
  UnitOfLength = 1e-09
  MeshOptions {
    MaximumSideLength = 40
  }
  Objects {    
    Polygon { 
      Name = "ComputationalDomain/Background" 
      DomainId = 1 
      Priority = -1 
      Points = [-100 -100, 100 -100, 100 100, -100 100] 
      Boundary { 
        Number = [1 3]
        BoundaryId = 1
      } 
      Boundary { 
        Number = [2 4]
        BoundaryId = 2
      } 
    }     
    Parallelogram { 
      Name = "Object"
      DomainId = 2
      Height = 200
      Width = 60
      RotationAngle = 120
      GlobalPosition = [40 -10]
    }
  }
}