FEM EquationFlux

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Flow equation

Heat equation

FEM

FEM EquationFlux
Menu location
Solve → Flux equation
Workbenches
FEM
Default shortcut
None
Introduced in version
0.19
See also
None

This equation is used to calculate the fluxes resulting usually from Poisson kind of equations. These include the Heat equation and the Electrostatic equation.

For info about the math of the equation, see the Elmer models manual, section Flux Computation.

Usage

1. After adding an Elmer solver as described here, select it in the tree view.
2. Either use the toolbar button or the menu Solve → Flux equation.
3. Now either add a heat equation (toolbar button or menu Solve → heat equation) or an electrostatic equation (toolbar button or menu Solve → Electrostatic equation). This is important because the flux equation needs the constraints set for these equastions.
4. When using the electrostatic equation, change the property DataFlux Coefficient to None. and the property DataFlux Variable to Potential.
5. Change the equation's solver settings or the general solver settings if necessary.

Solver Settings

For the general solver settings, see the Elmer solver settings.

The flux equation provides these special settings:

Constraint Information

The flux equation does not have own constraints. It takes the constraints from the Heat equation or the Electrostatic equation.

Flow equation

Heat equation

FEM

FEM

• FEM Analysis

• Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor

• Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)

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Constraints

• Electromagnetic: Electrostatic potential, Current density, Magnetization

• Fluid: Initial flow velocity, Initial pressure, Flow velocity

• Geometrical: Plane rotation, Section print, Transform

• Mechanical: Fixed, Displacement, Contact, Tie, Spring, Force, Pressure, Centrif, Self weight

• Thermal: Initial temperature, Heat flux, Temperature, Body heat source

• Overwrite Constants: Constant vacuum permittivity

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• Solve: CalculiX Standard, Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run

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• Utilities: Clipping plane, Remove clipping planes, Open FEM examples; Mesh clear, Mesh display info

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