Hello erveryone,

I first tried to calculate a geometry, which I solved successfully two-dimensionally, 3-dimensionally for comparison, before it gets more complicated.

I have tried a lot of settings, including completely different settings of solvers, which I found here in an example. But for the magnetic field AV I only get values close to 0.

The other values are comparable to the two-dimensional solution. Certainly the values are not the same, it is also another idealization and net geometry.

But can anyone tell me how i can get values for the paramter AV.

I attach the input and output file.

Very best regards,

Anton.

Version: 4.5.0 - Build 24.20.100.6292 on Windows 10 and

3.1 Mesa 18.2.8 on Linux 18.04, 64bit

Intel I7-8750H with 32 GB RAM an a fast SSD harddisk

Code: Select all

```
!!! case.sif !!!
Header
CHECK KEYWORDS Warn
Mesh DB "." "."
Include Path ""
Results Directory ""
End
Simulation
Max Output Level = 5
Coordinate System = Cartesian
Coordinate Scaling = Real 0.001 ! mm to meter
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
End
Constants
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 1"
Equation = 1
Material = 2
End
Body 2
Target Bodies(1) = 2
Name = "Body 2"
Equation = 1
Material = 3
End
Body 3
Target Bodies(1) = 3
Name = "Body 3"
Equation = 1
Material = 1
End
Solver 1
Equation = MgDyn
Procedure = "MagnetoDynamics" "WhitneyAVSolver"
Variable = AV
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 = 1000
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 2
Equation = MgDynPost
Procedure = "MagnetoDynamics" "MagnetoDynamicsCalcFields"
Potential Variable = String "AV"
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 = 1000
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
Calculate Magnetic Vector Potential = logical True
Calculate Magnetic Field Strength = logical True
Calculate Nodal Forces = logical true
End
!!! Save the fields to a file
Solver 3
Exec Solver = After Timestep
Equation = ResultOutput
Procedure = "ResultOutputSolve" "ResultOutputSolver"
Output File Name = "step"
Output Directory = "results"
! VTU format for ParaView with faces' IDs
Save Geometry Ids = logical True
Vtu Format = logical True
!Ascii Output = False
!Binary Output = logical True
!Single Precision = logical True
End
Solver 4
Exec Solver = After Timestep
Equation = SaveScalars
Procedure = "SaveData" "SaveScalars"
Filename = "results.dat"
Output Directory = "results"
Save Component Results = logical True
End
Equation 1
Name = "MGDyn"
Active Solvers(4) = 1 2 3 4
End
Material 1
Name = "air"
Relative Permeability = 1
End
Material 2
Name = "magnet1"
Relative Permeability = 1.216
Magnetization 2 = Real 942.0e3
End
Material 3
Name = "magnet3"
Relative Permeability = 1.216
Magnetization 2 = Real 666.0e3
Magnetization 1 = Real 666.0e3
End
Boundary Condition 1
Target Boundaries(1) = 4
Name = "farvield"
! Infinity BC = True
AV {e} = Real 0
! AV {e} 1 = Real 0
! AV {e} 2 = Real 0
End
Component 1
Name = string "force"
Master Bodies(1) = integer 2
Calculate Magnetic Force = Logical True
! Save Scalars = Logical True
End
```

Code: Select all

```
!!! case.out !!!
ELMER SOLVER (v 8.3) STARTED AT: 2019/08/23 12:19:25
ParCommInit: Initialize #PEs: 1
MAIN:
MAIN: =============================================================
MAIN: ElmerSolver finite element software, Welcome!
MAIN: This program is free software licensed under (L)GPL
MAIN: Copyright 1st April 1995 - , CSC - IT Center for Science Ltd.
MAIN: Webpage http://www.csc.fi/elmer, Email elmeradm@csc.fi
MAIN: Version: 8.3 (Rev: 432ee0dd, Compiled: 2018-12-18)
MAIN: Running one task without MPI parallelization.
MAIN: Running with just one thread per task.
MAIN: Lua interpreted linked in.
MAIN: =============================================================
MAIN:
MAIN:
MAIN: -------------------------------------
MAIN: Reading Model: case.sif
LoadInputFile: Scanning input file: case.sif
LoadInputFile: Loading input file: case.sif
Loading user function library: [MagnetoDynamics]...[WhitneyAVSolver_Init0]
Loading user function library: [MagnetoDynamics]...[MagnetoDynamicsCalcFields_Init0]
Loading user function library: [ResultOutputSolve]...[ResultOutputSolver_Init0]
Loading user function library: [SaveData]...[SaveScalars_Init0]
LoadMesh: Base mesh name: ./.
LoadMesh: Scaling coordinates: 1.000E-03 1.000E-03 1.000E-03
LoadMesh: Elapsed REAL time: 2.2330 (s)
MAIN: -------------------------------------
Loading user function library: [MagnetoDynamics]...[WhitneyAVSolver_Init]
Loading user function library: [MagnetoDynamics]...[WhitneyAVSolver_bulk]
Loading user function library: [MagnetoDynamics]...[WhitneyAVSolver]
OptimizeBandwidth: ---------------------------------------------------------
OptimizeBandwidth: Computing matrix structure for: mgdyn...done.
OptimizeBandwidth: Half bandwidth without optimization: 269367
OptimizeBandwidth:
OptimizeBandwidth: Bandwidth Optimization ...done.
OptimizeBandwidth: Half bandwidth after optimization: 13810
OptimizeBandwidth: ---------------------------------------------------------
Loading user function library: [MagnetoDynamics]...[MagnetoDynamicsCalcFields_Init]
Loading user function library: [MagnetoDynamics]...[MagnetoDynamicsCalcFields_bulk]
Loading user function library: [MagnetoDynamics]...[MagnetoDynamicsCalcFields]
OptimizeBandwidth: ---------------------------------------------------------
OptimizeBandwidth: Computing matrix structure for: mgdynpost...done.
OptimizeBandwidth: Half bandwidth without optimization: 40470
OptimizeBandwidth:
OptimizeBandwidth: Bandwidth Optimization ...done.
OptimizeBandwidth: Half bandwidth after optimization: 3303
OptimizeBandwidth: ---------------------------------------------------------
Loading user function library: [ResultOutputSolve]...[ResultOutputSolver_Init]
Loading user function library: [ResultOutputSolve]...[ResultOutputSolver_bulk]
Loading user function library: [ResultOutputSolve]...[ResultOutputSolver]
Loading user function library: [SaveData]...[SaveScalars_Init]
Loading user function library: [SaveData]...[SaveScalars_bulk]
Loading user function library: [SaveData]...[SaveScalars]
MAIN:
MAIN: -------------------------------------
MAIN: Steady state iteration: 1
MAIN: -------------------------------------
MAIN:
SingleSolver: Attempting to call solver
SingleSolver: Solver Equation string is: mgdyn
WhitneyAVSolver: Solving the AV equations with edge elements
MGDynAssembly: Elapsed REAL time: 3.2430 (s)
DefUtils::DefaultDirichletBCs: Setting Dirichlet boundary conditions
DefUtils::DefaultDirichletBCs: Dirichlet boundary conditions set
CRS_IncompleteLU: ILU(0) (Real), Starting Factorization:
CRS_IncompleteLU: ILU(0) (Real), NOF nonzeros: 4302723
CRS_IncompleteLU: ILU(0) (Real), filling (%) : 100
CRS_IncompleteLU: ILU(0) (Real), Factorization ready at (s): 0.11
10 0.4725E-01
20 0.3139E-02
30 0.5314E-03
40 0.5719E-04
50 0.2009E-05
60 0.4904E-06
70 0.4335E-07
80 0.1749E-08
90 0.2213E-09
98 0.9926E-10
ComputeChange: NS (ITER=1) (NRM,RELC): ( 0.27985351E-05 2.0000000 ) :: mgdyn
MGDynAssembly: Elapsed REAL time: 3.2150 (s)
DefUtils::DefaultDirichletBCs: Setting Dirichlet boundary conditions
DefUtils::DefaultDirichletBCs: Dirichlet boundary conditions set
CRS_IncompleteLU: ILU(0) (Real), Starting Factorization:
CRS_IncompleteLU: ILU(0) (Real), NOF nonzeros: 4302723
CRS_IncompleteLU: ILU(0) (Real), filling (%) : 100
CRS_IncompleteLU: ILU(0) (Real), Factorization ready at (s): 0.09
1 0.7576E-10
ComputeChange: NS (ITER=2) (NRM,RELC): ( 0.27985351E-05 0.11223008E-11 ) :: mgdyn
Loading user function library: [MagnetoDynamics]...[WhitneyAVSolver_post]
ComputeChange: SS (ITER=1) (NRM,RELC): ( 0.27985351E-05 2.0000000 ) :: mgdyn
SingleSolver: Attempting to call solver
SingleSolver: Solver Equation string is: mgdynpost
MagnetoDynamicsCalcFields: Computing postprocessed fields
WARNING:: GetPermittivity: Permittivity not defined in material, defaulting to that of vacuum
CRS_IncompleteLU: ILU(0) (Real), Starting Factorization:
CRS_IncompleteLU: ILU(0) (Real), NOF nonzeros: 582129
CRS_IncompleteLU: ILU(0) (Real), filling (%) : 100
CRS_IncompleteLU: ILU(0) (Real), Factorization ready at (s): 0.02
5 0.3783E-11
ComputeChange: NS (ITER=1) (NRM,RELC): ( 0.10064024 2.0000000 ) :: mgdynpost
5 0.4138E-11
ComputeChange: NS (ITER=2) (NRM,RELC): ( 0.28682764 0.96104684 ) :: mgdynpost
5 0.2846E-11
ComputeChange: NS (ITER=3) (NRM,RELC): ( 0.62167789E-01 1.2874659 ) :: mgdynpost
5 0.3727E-11
ComputeChange: NS (ITER=4) (NRM,RELC): ( 73921.307 1.9999966 ) :: mgdynpost
5 0.3896E-11
ComputeChange: NS (ITER=5) (NRM,RELC): ( 193490.62 0.89427059 ) :: mgdynpost
5 0.2792E-11
ComputeChange: NS (ITER=6) (NRM,RELC): ( 46163.342 1.2295000 ) :: mgdynpost
5 0.3674E-11
ComputeChange: NS (ITER=7) (NRM,RELC): ( 0.98640331E-03 1.9999999 ) :: mgdynpost
5 0.4255E-11
ComputeChange: NS (ITER=8) (NRM,RELC): ( 0.29531633E-03 1.0783746 ) :: mgdynpost
5 0.3727E-11
ComputeChange: NS (ITER=9) (NRM,RELC): ( 0.16007241E-02 1.3769831 ) :: mgdynpost
MagnetoDynamicsCalcFields: Eddy current power: 0.0000000000000000
MagnetoDynamicsCalcFields: (Electro)Magnetic Field Energy: 7.1543214362065717
Loading user function library: [MagnetoDynamics]...[MagnetoDynamicsCalcFields_post]
ComputeChange: SS (ITER=1) (NRM,RELC): ( 0.16007241E-02 2.0000000 ) :: mgdynpost
SingleSolver: Attempting to call solver
SingleSolver: Solver Equation string is: resultoutput
ResultOutputSolver: -------------------------------------
ResultOutputSolve: Saving with prefix: step
ResultOutputSolver: Creating list for saving - if not present
CreateListForSaving: Field Variables for Saving
ResultOutputSolver: Saving in unstructured VTK XML (.vtu) format
VtuOutputSolver: Saving results in VTK XML format with prefix: step
VtuOutputSolver: Saving number of partitions: 1
WriteVtuFile: Writing variable: magnetic flux density e
WriteVtuFile: Writing variable: magnetic vector potential e
WriteVtuFile: Writing variable: magnetic field strength e
WriteVtuFile: Writing variable: nodal force e
ResultOutputSolver: -------------------------------------
Loading user function library: [ResultOutputSolve]...[ResultOutputSolver_post]
SingleSolver: Attempting to call solver
SingleSolver: Solver Equation string is: savescalars
SaveScalars: -----------------------------------------
SaveScalars: Saving scalar values of various kinds
SaveScalars: Saving names of values to file: results/results.dat.names
SaveScalars: Saving values to file: results/results.dat
Loading user function library: [SaveData]...[SaveScalars_post]
ElmerSolver: *** Elmer Solver: ALL DONE ***
ElmerSolver: The end
SOLVER TOTAL TIME(CPU,REAL): 20.47 20.47
ELMER SOLVER FINISHED AT: 2019/08/23 12:19:46
```