I try to simulate the magnetix flux density B of two parallel arranged magnets (Nd, N52). Magnetization in the same direction and perpendicular to the axis connecting both magnets . I did it with FEMM and Elmer and got different results for the strength of B. That is in the middle between both magnets 530mT for FEMM (non-linear H-B curve) and 400 mT for Elmer (non-linear) respectively 430 mT for Elemer (linear). Magnet properties are taken from FEMM. Does someone has experience with both programs and knows the problem? Thanks
.vtu-file is attached and following the Elmer sif-file. H-B curve is in a separate file.
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Header
CHECK KEYWORDS Warn
Mesh DB "." "."
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.vtu
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 = "Body Property 1"
Equation = 1
Material = 3
End
Body 2
Target Bodies(1) = 2
Name = "Body Property 2"
Equation = 1
Material = 3
End
Body 3
Target Bodies(1) = 3
Name = "Body Property 3"
Equation = 1
Material = 1
End
Solver 2
Equation = MgDyn2DPost
Procedure = "MagnetoDynamics2D" "BSolver"
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 = Iterative
Linear System Iterative Method = BiCGStab
Linear System Max Iterations = 500
Linear System Convergence Tolerance = 1.0e-10
BiCGstabl polynomial degree = 2
Linear System Preconditioning = ILU0
Linear System ILUT Tolerance = 1.0e-3
Linear System Abort Not Converged = False
Linear System Residual Output = 10
Linear System Precondition Recompute = 1
End
Solver 1
Equation = MgDyn2D
Procedure = "MagnetoDynamics2D" "MagnetoDynamics2D"
Variable = Potential
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 = Iterative
Linear System Iterative Method = BiCGStab
Linear System Max Iterations = 500
Linear System Convergence Tolerance = 1.0e-10
BiCGstabl polynomial degree = 2
Linear System Preconditioning = ILU0
Linear System ILUT Tolerance = 1.0e-3
Linear System Abort Not Converged = False
Linear System Residual Output = 10
Linear System Precondition Recompute = 1
End
Equation 1
Name = "MgDyn2D"
Active Solvers(2) = 2 1
End
Equation 2
Name = "MgDyn2DPost"
End
Material 1
Name = "Air"
Relative Permeability = 1
End
Material 2
Name = "N52"
Relative Permeability = 1.05
Magnetization 1 = 956180
Electric Conductivity = 0.667
H-B Curve = Variable "nonlin"
include HB_N52
End
End
Boundary Condition 1
Target Boundaries(1) = 3
Name = "FarField"
Infinity BC = True
End