FEM ElectricChargeDensity/en

Description

Creates electric charge density load. To be used together with the Electrostatic equation.

introduced in 1.1: Works also with the refactored CalculiX solver object.

Electric charge density boundary condition in the capacitance of concentric cylinders example

Usage

1. There are several ways to invoke the command:
   • Press the Electric Charge Density button.
   • Select the Model → Electromagnetic Boundary Conditions → Electric Charge Density option from the menu.
2. Select a mode:
   • Interface - free surface charge density (to be applied to surfaces in 3D analyses and edges in 2D analyses) allowing modeling of charged layers, equivalent to Electric Flux Density in Electrostatic potential boundary condition, specify Density
   • Source - free volume charge density (to be applied to solids in 3D analyses and surfaces in 2D analyses), specify Density
   • Total Interface - total charge distributed across the free surface, specify Total Charge
   • Total Source - total charge distributed across the free volume, specify Total Charge.
     • introduced in 1.2: The Concentrated checkbox makes it possible to switch from distributed to concentrated load and apply it to edges and vertices if CalculiX is used as the solver.
3. Press the Add button.
4. In the 3D View select the object the load should be applied to. introduced in 1.1: To remove objects from the selection, press the Remove button.

Options

The dialog offers the following settings:

• Interface Charge Density: To specify interface charge density in C/m^2.
• Mode: To choose between the Interface, Source, Total Interface and Total Source modes.
• Source Charge Density: To specify source charge density in C/m^3.
• Total Charge: To specify total charge in C.