FEM EquationFlux: Difference between revisions

Revision as of 17:09, 16 August 2022

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Flow equation

Heat equation

FEM

Menu location
FEM EquationFlux
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

After adding an Elmer solver as described here, select it in the tree view.
Either use the toolbar button or the menu Solve → Flux equation.
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.
When using the electrostatic equation, change the property DataFlux Coefficient to None. and the property DataFlux Variable to Potential.
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.

Results

The available results depend on the solver settings. If none of them was set to true, nothing is calculated. Otherwise also the corresponding results will be available.

The resulting flux is either the heat flux ${\rm {W/m^{2}}}$ (misleadingly named "temperature flux") or the potential flux in ${\rm {W/m^{2}}}$ ( ${\rm {A\cdot V/m^{2}}}$ ).

Flow equation

Heat equation

FEM

FEM Analysis

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

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

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

Mesh: Mesh Netgen, Mesh GMSH, Mesh boundary layer, Mesh region, Mesh group, Nodes set, Mesh to mesh

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

Results: Purge, Show; Postprocessing: Apply changes, Pipeline from result, Warp filter, Scalar clip filter, Function cut filter, Region clip filter, Contours filter, Line clip filter, Stress linearization plot, Data at point clip filter, Filter function plane, Filter function sphere, Filter function cylinder, Filter function box

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

Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types

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Revision as of 16:23, 16 August 2022 (view source) Uwestoehr (talk \| contribs) (→‎Constraint Information: add results info) ← Older edit		Revision as of 17:09, 16 August 2022 (view source) Uwestoehr (talk \| contribs) (→‎Results: correct wrong info) Newer edit →
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	The available results depend on the [[#Solver_Settings\|solver settings]]. If none of them was set to ''true'', nothing is calculated. Otherwise also the corresponding results will be available.		The available results depend on the [[#Solver_Settings\|solver settings]]. If none of them was set to ''true'', nothing is calculated. Otherwise also the corresponding results will be available.

	The resulting flux is either the heat flux <math>\rm W/m^2</math> or the potential flux in <math>\rm V/m^2</math>.		The resulting flux is either the heat flux <math>\rm W/m^2</math> (misleadingly named "temperature flux") or the potential flux in <math>\rm W/m^2</math> (<math>\rm A\cdot V/m^2</math>).