In brief:

I have multiple Domains (14 bodies) in a simulation and I want to apply the potential/joule heating JUST in three bodies (domains).

However, the heat flux shall propagate through every domain and lead to thermal stresses in the overall structure.

I like to set up the following:

1. potential/electric field evolves an electric current

2. electric current results in liberated heat by joule heating

3. the liberated heat drives the thermal expansion und results in thermal stresses

I do need to say, that I reviewed multiple examples for elmer. [e.g. Tutorial 9: Thermal actuator driven with electrostatic currents, http://www.nic.funet.fi/index/elmer/doc ... nonGUI.pdf, 2017.Sept.11]

However, I did not find any example that explains how to.

I know it must be pretty simple - nevertheless I'd appreciate if someone could give me a hint...

Cheers

Manuel

Code: Select all

```
Header
CHECK KEYWORDS Warn
Mesh DB "." "."
Include Path ""
Results Directory ".\output"
End
Simulation
Max Output Level = 5
Coordinate System = Cartesian
Coordinate Mapping(3) = 1 2 3
Simulation Type = Transient
Steady State Max Iterations = 10 !1 is weak coupling, 10 is strong couling
Output Intervals = 1
Timestepping Method = BDF
BDF Order = 2
Timestep intervals = 2 ! is the overall time
Timestep Sizes = 1e-1 ! is the time step size
Solver Input File = case.sif
Post File = case.vtu
End
Constants
Gravity(4) = 0 0 0 9.82
Stefan Boltzmann = 5.67e-08
! Permittivity Of Vacuum = 8.8542e-12 ! C^2/Nm^2
Permittivity Of Vacuum = 1.0 ! manipulation for conducting material
Boltzmann Constant = 1.3807e-23
Unit Charge = 1.602e-19
End
Body 1
Target Bodies(3) = 1 2 3
Equation = 1
Material = 1
Body Force = 1
Initial condition = 1
End
Body 2
Target Bodies(2) = 7 14
Equation = 1
Material = 2
Initial condition = 2
End
Body 3
Target Bodies(3) = 4 5 6
Equation = 1
Material = 3
Initial condition = 2
End
Body 4
Target Bodies(6) = 8 9 10 11 12 13
Equation = 1
Material = 4
Initial condition = 2
End
Material 1
Electric Conductivity = Variable Temperature
Real
298.0 0.62500e5
398.0 0.82500e5
End
Heat expansion Coefficient = 20.0e-6
Heat Conductivity = 3.4
Relative Permittivity = 1.0005
Heat Capacity = 1278.0
Mesh Poisson ratio = 0.35
Density = 2780.0
Poisson ratio = 0.35
Youngs modulus = 7.405e9
End
Material 2
Electric Conductivity = Variable Temperature
Real
298.0 0.62500e5
398.0 0.82500e5
End
Heat expansion Coefficient = 21.0e-6
Heat Conductivity = 730
Heat Capacity = 921.0
Mesh Poisson ratio = 0.33
Density = 2700.0
Poisson ratio = 0.33
Youngs modulus = 70.0e9
End
Material 3
Electric Conductivity = Variable Temperature
Real
298.0 0.62500e5
398.0 0.82500e5
End
Heat expansion Coefficient = 21.0e-6
Heat Conductivity = 1.0
Heat Capacity = 921.0
Mesh Poisson ratio = 0.33
Density = 2700.0
Poisson ratio = 0.33
Youngs modulus = 70.0e9
End
Material 4
Electric Conductivity = Variable Temperature
Real
298.0 0.62500e5
398.0 0.82500e5
End
Heat expansion Coefficient = 3.43e-6 ! e-3 is normal, but looks crazy. change does not effect significantly
Heat Conductivity = 0.0257
Heat Capacity = 1005.0
!Mesh Poisson ratio = 0.33
Density = 1205.0
Poisson ratio = 0.33
Youngs modulus = 1.0e5
End
Initial Condition 1
Potential = 0
Displacement 1 = 0
Displacement 2 = 0
Displacement 3 = 0
Temperature = 298
End
Initial Condition 2
Displacement 1 = 0
Displacement 2 = 0
Displacement 3 = 0
Temperature = 298
End
Body Force 1
Heat Source = Equals Joule Heating
End
Boundary Condition 1
Target Boundaries(2) = 1 2
Name = "Sym"
Heat Flux = 0
Displacement 1 = 0
End
Boundary Condition 2
Target Boundaries(3) = 3 5 7
Name = "TopPot"
Potential = 30.7
End
Boundary Condition 3
Target Boundaries(3) = 4 6 8
Name = "BotPot"
Potential = 0.0
End
Boundary Condition 4
Target Boundaries(2) = 9 10
Name = "Boun"
Displacement 3 = 0
Temperature = 298
End
Equation 1
Active Solvers(4) = 1 2 3 4
End
Solver 1
Equation = Result Output
Output Format = Vtu
Output File Name = case
Procedure = "ResultOutputSolve" "ResultOutputSolver"
Exec Solver = Always
End
Solver 2
Equation = Stat Current Solver
Procedure = "StatCurrentSolve" "StatCurrentSolver"
Variable = Potential
Variable DOFs = 1
Calculate Joule Heating = True
Calculate Electric Conductivity = True
Linear System Solver = Iterative
Linear System Iterative Method = CG
Linear System Preconditioning = ILU3
Linear System Max Iterations = 300
Linear System Convergence Tolerance = 1.0e-8
Nonlinear System Max Iterations = 1
Nonlinear System Convergence Tolerance = 1.0-6
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-12
Nonlinear System Relaxation Factor = 1.0
Steady State Convergence Tolerance = 1.0e-6
End
Solver 3
Equation = Heat Equation
Variable = Temperature
Variable DOFs = 1
!Calculate Joule Heating = True
Linear System Solver = Iterative
Linear System Iterative Method = BiCGStab
Linear System Preconditioning = ILU1
Linear System Max Iterations = 350
Linear System Convergence Tolerance = 1.0e-9
Nonlinear System Max Iterations = 1
Nonlinear System Convergence Tolerance = 1.0e-07
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-12
Nonlinear System Relaxation Factor = 0.5
Steady State Convergence Tolerance = 1.0e-07
End
Solver 4
Equation = Stress Analysis
Linear System Solver = Direct
Variable = Displacement
Variable Dofs = 3
Calculate Stresses = True
Linear System Iterative Method = "BiCGStab"
Linear System Max Iterations = 500
Linear System Convergence Tolerance = 1.0e-08
Linear System Abort Not Converged = True
Linear System Preconditioning = "ILU0"
Linear System Residual Output = 1
Steady State Convergence Tolerance = 1.0e-05
Nonlinear System Convergence Tolerance = 1.0e-05
Nonlinear System Max Iterations = 1
Nonlinear System Newton After Iterations = 3
Nonlinear System Newton After Tolerance = 1.0e-02
Nonlinear System Relaxation Factor = 1
Linear System Precondition Recompute = 1
End
```