Temperature Expansion Problem
Posted: 13 Feb 2020, 17:05
Hello
,
maybe someone can help me with a problem solving the temperature expansion of a Rod (diameter: 5mm, length: 100mm)
The rod is fastened on one side.
Delta temperature is 100K with an coefficient of thermal expansion of 11.1e-6.
Of my hand bill i´ve got an expansion of 0,111mm.
The Result of the Simulation states, that the expansion is nearly half of that with 0,058mm (0,58e-5m).
I´ve got two boundary conditions. One for the fastened side with an temperature of 100K, the other one for the rest of the rod with just the temperature.
I did vary the temperature and the expansion coefficient(seperatly) with the results did vary proportionally to the variations.
I think i´m missing some options.
thanks for your attention.
here is my sif file:
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
Coordinate Scaling = 0.001
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 = "TEMP1"
Equation = 1
Material = 1
End
Solver 1
Equation = Linear elasticity
Procedure = "StressSolve" "StressSolver"
Variable = -dofs 3 Displacement
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 = 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 = 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
Equation 1
Name = "Heat"
Calculate Stresses = True
Active Solvers(2) = 1 2
End
Material 1
Name = "Steel_1"
Heat expansion Coefficient = 11.1e-6
Heat Conductivity = 37.2
Sound speed = 5100.0
Heat Capacity = 461.0
Density = 7850.0
Poisson ratio = 0.3
Youngs modulus = 210.0e9
End
Boundary Condition 1
Target Boundaries(2) = 1 3
Name = "Temperature"
Temperature Condition = 1
Temperature = 100
End
Boundary Condition 2
Target Boundaries(1) = 2
Name = "Fastened"
Displacement 3 = 0
Displacement 2 = 0
Displacement 1 = 0
Temperature Condition = 1
Temperature = 100
End
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maybe someone can help me with a problem solving the temperature expansion of a Rod (diameter: 5mm, length: 100mm)
The rod is fastened on one side.
Delta temperature is 100K with an coefficient of thermal expansion of 11.1e-6.
Of my hand bill i´ve got an expansion of 0,111mm.
The Result of the Simulation states, that the expansion is nearly half of that with 0,058mm (0,58e-5m).
I´ve got two boundary conditions. One for the fastened side with an temperature of 100K, the other one for the rest of the rod with just the temperature.
I did vary the temperature and the expansion coefficient(seperatly) with the results did vary proportionally to the variations.
I think i´m missing some options.
thanks for your attention.
here is my sif file:
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
Coordinate Scaling = 0.001
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 = "TEMP1"
Equation = 1
Material = 1
End
Solver 1
Equation = Linear elasticity
Procedure = "StressSolve" "StressSolver"
Variable = -dofs 3 Displacement
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 = 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 = 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
Equation 1
Name = "Heat"
Calculate Stresses = True
Active Solvers(2) = 1 2
End
Material 1
Name = "Steel_1"
Heat expansion Coefficient = 11.1e-6
Heat Conductivity = 37.2
Sound speed = 5100.0
Heat Capacity = 461.0
Density = 7850.0
Poisson ratio = 0.3
Youngs modulus = 210.0e9
End
Boundary Condition 1
Target Boundaries(2) = 1 3
Name = "Temperature"
Temperature Condition = 1
Temperature = 100
End
Boundary Condition 2
Target Boundaries(1) = 2
Name = "Fastened"
Displacement 3 = 0
Displacement 2 = 0
Displacement 1 = 0
Temperature Condition = 1
Temperature = 100
End