### Elmer+Paraview

Posted:

**09 Nov 2020, 09:16**To whom it may concern

I am new to Elmer. I want to model the gas flow by the pressure difference in the tube. I want to use the Perfect Gas model in Elmer. But I faced errors when I used the Perfect Gas model. I would be pleased if you help with this issue. I attached my SIF file for your reference.

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 = 10

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 1"

Equation = 1

Material = 1

Initial condition = 1

End

Body 2

Target Bodies(1) = 2

Name = "Body 2"

Equation = 1

Material = 2

Initial condition = 2

End

Body 3

Target Bodies(1) = 3

Name = "Body 3"

Equation = 2

Material = 3

Initial condition = 3

End

Body 4

Target Bodies(1) = 4

Name = "Body 4"

Equation = 2

Material = 3

Initial condition = 3

End

Body 5

Target Bodies(1) = 5

Name = "Body 5"

Equation = 1

Material = 1

Initial condition = 3

End

Body 6

Target Bodies(1) = 6

Name = "Body 6"

Equation = 2

Material = 3

Initial condition = 3

End

Body 7

Target Bodies(1) = 7

Name = "Body 7"

Equation = 2

Material = 3

Initial condition = 3

End

Body 8

Target Bodies(1) = 8

Name = "Body 8"

Equation = 1

Material = 1

Initial condition = 4

End

Body 9

Target Bodies(1) = 9

Name = "Body 9"

Equation = 1

Material = 2

Initial condition = 5

End

Solver 3

Equation = Heat Equation

Procedure = "HeatSolve" "HeatSolver"

Variable = Temperature

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 2

Equation = K-Epsilon

Procedure = "KESolver" "KESolver"

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 = Navier-Stokes

Procedure = "FlowSolve" "FlowSolver"

Variable = Flow Solution[Velocity:3 Pressure:1]

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 = "Just Heat"

Convection = Computed

Active Solvers(1) = 3

End

Equation 2

Name = "Heat+Navier+K-epsilon"

Convection = Computed

Active Solvers(3) = 2 1 3

End

Material 1

Name = "Steel"

Heat Conductivity = 10

Density = 8000

End

Material 2

Name = "Solid Mg"

Density = 1500

Viscosity = 0.0009

Heat Conductivity = 88

End

Material 3

Name = "Gas Mg"

Density = 0.01

Viscosity = 0.00088

Heat Conductivity = 85

Compressibility Model = Perfect Gas

End

Initial Condition 1

Name = "Bottom Steel"

Temperature = Variable " coordinate 3 "

Real MATC " 1123-3893.8 * tx "

Kinetic Dissipation = 1.0e-4

Kinetic Energy = 0.00457

End

Initial Condition 2

Name = "Solid Mg"

Kinetic Dissipation = 1.0e-4

Kinetic Energy = 0.00457

Temperature = Variable " coordinate 3 "

Real MATC " 1084-442.5 *(tx-0.01)

End

Initial Condition 3

Name = "Gas Mg"

Temperature = 1073.5

Kinetic Energy = 0.00457

Kinetic Dissipation = 1.0e-4

End

Initial Condition 4

Name = "Top Steel"

Kinetic Dissipation = 1.0e-4

Temperature = Variable " coordinate 3 "

Real MATC " 1073-3893.8 * (tx-0.31) "

Kinetic Energy = 0.00457

End

Initial Condition 5

Name = "Top Solid Mg"

Kinetic Energy = 0.00457

Kinetic Dissipation = 1.0e-4

Temperature = Variable " coordinate 3 "

Real MATC" 1034-442.5*(tx-0.32)

End

Boundary Condition 1

Target Boundaries(1) = 10

Name = "Bottom"

Temperature = 1123

End

Boundary Condition 2

Target Boundaries(2) = 16 41

Name = "Interface ( Solid/Gas)"

Pressure 3 = Variable " temperature "

Real MATC " exp(-7750/(tx)+12.79-1.41*log(tx))*101300/760"

Heat Flux = Variable " velocity 3 "

Real MATC " -127400*24*0.01*tx "

End

Boundary Condition 3

Target Boundaries(11) = 17 24 26 28 29 30 35 36 37 38 39

Name = "Walls"

Noslip wall BC = True

End

Boundary Condition 4

Target Boundaries(1) = 46

Name = "Top"

Temperature = 1023

End

I am new to Elmer. I want to model the gas flow by the pressure difference in the tube. I want to use the Perfect Gas model in Elmer. But I faced errors when I used the Perfect Gas model. I would be pleased if you help with this issue. I attached my SIF file for your reference.

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 = 10

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 1"

Equation = 1

Material = 1

Initial condition = 1

End

Body 2

Target Bodies(1) = 2

Name = "Body 2"

Equation = 1

Material = 2

Initial condition = 2

End

Body 3

Target Bodies(1) = 3

Name = "Body 3"

Equation = 2

Material = 3

Initial condition = 3

End

Body 4

Target Bodies(1) = 4

Name = "Body 4"

Equation = 2

Material = 3

Initial condition = 3

End

Body 5

Target Bodies(1) = 5

Name = "Body 5"

Equation = 1

Material = 1

Initial condition = 3

End

Body 6

Target Bodies(1) = 6

Name = "Body 6"

Equation = 2

Material = 3

Initial condition = 3

End

Body 7

Target Bodies(1) = 7

Name = "Body 7"

Equation = 2

Material = 3

Initial condition = 3

End

Body 8

Target Bodies(1) = 8

Name = "Body 8"

Equation = 1

Material = 1

Initial condition = 4

End

Body 9

Target Bodies(1) = 9

Name = "Body 9"

Equation = 1

Material = 2

Initial condition = 5

End

Solver 3

Equation = Heat Equation

Procedure = "HeatSolve" "HeatSolver"

Variable = Temperature

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 2

Equation = K-Epsilon

Procedure = "KESolver" "KESolver"

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 = Navier-Stokes

Procedure = "FlowSolve" "FlowSolver"

Variable = Flow Solution[Velocity:3 Pressure:1]

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 = 1

Nonlinear System Newton After Iterations = 3

Nonlinear System Newton After Tolerance = 1.0e-3

Nonlinear System Relaxation Factor = 0.00001

Linear System Solver = Iterative

Linear System Iterative Method = BiCGStabl

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 = "Just Heat"

Convection = Computed

Active Solvers(1) = 3

End

Equation 2

Name = "Heat+Navier+K-epsilon"

Convection = Computed

Active Solvers(3) = 2 1 3

End

Material 1

Name = "Steel"

Heat Conductivity = 10

Density = 8000

End

Material 2

Name = "Solid Mg"

Density = 1500

Viscosity = 0.0009

Heat Conductivity = 88

End

Material 3

Name = "Gas Mg"

Density = 0.01

Viscosity = 0.00088

Heat Conductivity = 85

Compressibility Model = Perfect Gas

End

Initial Condition 1

Name = "Bottom Steel"

Temperature = Variable " coordinate 3 "

Real MATC " 1123-3893.8 * tx "

Kinetic Dissipation = 1.0e-4

Kinetic Energy = 0.00457

End

Initial Condition 2

Name = "Solid Mg"

Kinetic Dissipation = 1.0e-4

Kinetic Energy = 0.00457

Temperature = Variable " coordinate 3 "

Real MATC " 1084-442.5 *(tx-0.01)

End

Initial Condition 3

Name = "Gas Mg"

Temperature = 1073.5

Kinetic Energy = 0.00457

Kinetic Dissipation = 1.0e-4

End

Initial Condition 4

Name = "Top Steel"

Kinetic Dissipation = 1.0e-4

Temperature = Variable " coordinate 3 "

Real MATC " 1073-3893.8 * (tx-0.31) "

Kinetic Energy = 0.00457

End

Initial Condition 5

Name = "Top Solid Mg"

Kinetic Energy = 0.00457

Kinetic Dissipation = 1.0e-4

Temperature = Variable " coordinate 3 "

Real MATC" 1034-442.5*(tx-0.32)

End

Boundary Condition 1

Target Boundaries(1) = 10

Name = "Bottom"

Temperature = 1123

End

Boundary Condition 2

Target Boundaries(2) = 16 41

Name = "Interface ( Solid/Gas)"

Pressure 3 = Variable " temperature "

Real MATC " exp(-7750/(tx)+12.79-1.41*log(tx))*101300/760"

Heat Flux = Variable " velocity 3 "

Real MATC " -127400*24*0.01*tx "

End

Boundary Condition 3

Target Boundaries(11) = 17 24 26 28 29 30 35 36 37 38 39

Name = "Walls"

Noslip wall BC = True

End

Boundary Condition 4

Target Boundaries(1) = 46

Name = "Top"

Temperature = 1023

End