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/ElmerTutorials_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