介电屏蔽边界条件用于静电场建模仿真

2 | DIELECTRIC SHIELDING COMPARISON

Introduction

The dielectric shielding boundary condition is meant to approximate a thin layer of

material with high relative permittivity compared to its surroundings. This boundary

condition is available for electrostatic field modeling. This example compares the dielectric

shielding boundary condition to a full-fidelity model and discusses the range of

applicability of this boundary condition.

Model Definition

The situation being modeled is shown in Figure 1. Two parallel plates in free space

(relative permittivity, ε

Between these plates there is a 1 cm outer diameter circular inclusion with a wall thickness

of 1mm. The walls are made of a high dielectric (ε

The walls of this inclusion are modeled two ways, first using a full fidelity model that

shielding condition, the total volume of the surrounding material is slightly larger, since

the thickness of the wall is not being explicitly modeled.

The electric field and isolines of the voltage is plotted in Figure 2. The field lines can be

observed to deform toward the inclusion. The solutions for the full fidelity and electric

shielding

model agree well.

Figure 2: Isolines of the voltage field, and streamlines of the electric field are plotted. The lines

are colored according to the strength of the electric field, and the background gray-scale plot is

identical.

The dielectric shielding boundary condition can be used in cases where the thickness of

4 | DIELECTRIC SHIELDING COMPARISON

From the File menu, choose New.

In the New window, click Model Wizard.

1 In the Model Wizard window, click 2D.

2 In the Select Physics tree, select AC/DC>Electric Fields and Currents>Electrostatics (es).

3 Click Add.

4 Click Study.

5 In the Select Study tree, select General Studies>Stationary.

6 Click Done.

2 In the Settings window for Parameters, locate the Parameters section.

3 In the table, enter the following settings:

1 In the Geometry toolbar, click Rectangle.

2 In the Settings window for Rectangle, locate the Size and Shape section.

3 In the Width text field, type 8.

4 In the Height text field, type 10.

5 Locate the Position section. In the x text field, type 0.1.

6 In the y text field, type -5.

1 In the Geometry toolbar, click Rectangle.

2 In the Settings window for Rectangle, locate the Size and Shape section.

3 In the Width text field, type 3.5.

4 Locate the Position section. In the x text field, type 0.1.

5 In the y text field, type 2.

1 In the Geometry toolbar, click Transforms and choose Copy.

2 Select the object fil1 only.