Plasma Module Updates

For users of the Plasma Module, COMSOL Multiphysics® version 5.5 brings improved electron energy distribution function (EEDF) functionality, a new physics interface for modeling electrostatic precipitators, and a new physics interface to detect whether electrical breakdown will occur. Learn about these and more plasma updates below.

Electron Energy Distribution Function

Previously, the electron energy distribution function (EEDF) needed to be an assumed function. In version 5.5, it is possible to compute the EEDF for space-dependent models using a two-term approximation of the Boltzmann equation. You can see this new functionality in the GEC ICP Reactor Coupled with the Two-Term Boltzmann Equation model.

A 1D plot of the EEDF versus energy at different vertical heights in a GEC reference cell. EEDF in a GEC reference cell The computed electron energy distribution function at different vertical heights in a GEC reference cell.

New Tools for Modeling Electrostatic Precipitators

A new physics interface, Corona Discharge, uses an approximate method to compute the charge distribution, making it easier to solve than a fully self-consistent plasma model. A new Charge Accumulation feature is available in the Particle Tracing Module that computes the accumulation of charge on particles as they travel through a fluid with nonzero space charge density. These tools can be used to efficiently model electrostatic precipitators. You can see these new features in the Electrostatic Precipitator and Positive and Negative Corona Discharges models.

A surface plot visualizing the space charge density distribution in a rainbow color table. Space charge density surface plot Space charge density distribution in an electrostatic precipitator.

New Physics Interface for Detecting Electrical Breakdown

A new physics interface, Electrical Breakdown Detection, integrates the Townsend coefficient along electric field lines to predict whether electrical breakdown will occur. This method is faster than a self-consistent plasma model and can show where electrical breakdown could occur in a given design. You can see this new feature in the Electrical Breakdown Between Two Spheres model.

A model of the outline of two spheres with electric field lines between them shown in blue, teal, and magenta. Example that uses the Electrical Breakdown Detection interface Electric field lines (streamlines) and breakdown predictor (surface) at the exact voltage at which streamer formation will occur.

New Tutorial Models

Version 5.5 brings several new tutorial models.

Electrostatic Precipitator
A 1D plot of the particle collection efficiency from 0 to 1 versus particle radius from 0 to 5 micrometers. Particle collection efficiency vs. particle radius Particle collection efficiency vs. particle radius in an electrostatic precipitator.

Application Library Title:
electrostatic_precipitator
Download from the Application Gallery

Positive and Negative Corona Discharges
A 1D plot of space charge density from -0.5 to 1.3 versus r-coordinate from 0 to 10 centimeters. Space charge density vs. r-coordinate Space charge density profile using an approximate method and fully self-consistent model for a positive and negative corona.

Application Library Title:
positive_and_negative_corona_discharges
Download from the Application Gallery

DC Glow Discharge Coupled with the Two-Term Boltzmann Equation
A 1D plot of EEDF versus energy with a blue solid line for two-term Boltzmann and a green dashed line for Maxwellian. EEDF vs. energy: Computed and Maxwellian EEDF Comparison of the computed and Maxwellian EEDF at two different locations in a positive column.

Application Library Title:
positive_column_1d_boltzmann
Download the Application Gallery

GEC ICP Reactor Coupled with the Two-Term Boltzmann Equation
A 1D plot of EEDF versus energy at different z locations in a GEC reference cell. EEDF vs. energy: GEC reference cell Plot of the EEDF at various locations in a GEC reference cell.

Application Library Title:
argon_gec_icp_boltzmann
Download from the Application Gallery

Electrical Breakdown Between Two Spheres
A model of two spheres with the reduced electric field shown as streamlines in a rainbow color table. Electrical breakdown between two spheres Surface plot of the integrated Townsend coefficient. The streamlines show the direction and magnitude of the reduced electric field.

Application Library Title:
breakdown_between_spheres
Download from the Application Gallery