FEM ConstraintInitialPressure

Constraint initial flow velocity

Constraint flow velocity

FEM

Description

Creates an initial pressure condition for a fluid flow analysis.

Usage

1. There are several ways to invoke the command:
   • Press the Initial Pressure Condition button.
   • Select the Model → Fluid Boundary Conditions → Initial Pressure Condition option from the menu.
2. Enter an initial pressure value.
3. Press the Add button. For a 3D analysis, select a 'solid' (body) from your model, for a 2D analysis select a face. introduced in 1.1: To remove objects from the selection, press the Remove button.

Notes

For simple analyses, it is not necessary to specify the initial pressure, however also in these cases it is recommended as best practice.

Constraint initial flow velocity

Constraint flow velocity

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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• 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

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

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