I'm running a very simple eigenvalue simulation, getting the modes of vibration for a 3d solid box restricted on one face.
I'm running into the issue that when I add a boundary condition to say, boundary number 5, it is applied to both surface 5 and line 5. What am I doing wrong here?
I've attached my code, as well as a paraview screenshot where the displacement of surface 6 or the right and line 6 on the left are both kept at 0.
The box is meshed using gmsh, and then converted using ElmerGrid. I'm running the Windows ElmerSolver Version: 8.2 (Rev: Release, Compiled: 2016-03-15)
Thanks for your help.
Jerome.
case.sif:
Code: Select all
Header
CHECK KEYWORDS Warn
Mesh DB "." "plinth"
Include Path ""
Results Directory ""
End
Simulation
Max Output Level = 5
Coordinate System = Cartesian
Coordinate Mapping(3) = 1 2 3
Simulation Type = Steady state
Steady State Max Iterations = 1
Output Intervals = 1
Timestepping Method = BDF
BDF Order = 1
Solver Input File = case.sif
Post File = case.ep
End
Constants
Gravity(4) = 0 -1 0 9.82
Stefan Boltzmann = 5.67e-08
Permittivity of Vacuum = 8.8542e-12
Boltzmann Constant = 1.3807e-23
Unit Charge = 1.602e-19
End
Body 1
Target Bodies(1) = 1
Name = "plinth"
Equation = 1
Material = 1
End
Solver 1
Equation = Linear elasticity
Eigen System Values = 35
Procedure = "StressSolve" "StressSolver"
Variable = -dofs 3 Displacement
Eigen System Select = Smallest magnitude
Eigen Analysis = True
Exec Solver = Always
Stabilize = True
Bubbles = False
Lumped Mass Matrix = False
Optimize Bandwidth = True
Steady State Convergence Tolerance = 1.0e-5
Nonlinear System Convergence Tolerance = 1.0e-7
Nonlinear System Max Iterations = 20
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-3
Nonlinear System Relaxation Factor = 1
Linear System Solver = Direct
Linear System Direct Method = Umfpack
End
Solver 2
Exec Solver = after timestep
Equation = "result output"
Procedure = "ResultOutputSolve" "ResultOutputSolver"
Output File Name = "case"
Output Format = String "vtu"
Binary Output = True
Single Precision = True
End
Equation 1
Name = "Equation 1"
Active Solvers(2) = 1 2
End
Material 1
Name = "Concrete"
Mesh Poisson ratio = 0.2
Density = 2300.0
Poisson ratio = 0.2
Youngs modulus = 40.0e9
End
Boundary Condition 1
Target Boundaries(1) = 6
Name = "fixed"
Displacement 3 = 0
Displacement 2 = 0
Displacement 1 = 0
End