Overview of the User’s Guide
The Plasma Module User’s Guide gets you started with modeling using COMSOL Multiphysics. The information in this guide is specific to this module. Instructions how to use COMSOL in general are included with the COMSOL Multiphysics Reference Manual.
As detailed in the section Where Do I Access the Documentation and Application Libraries? this information can also be searched from the COMSOL Multiphysics software Help menu.
Data Requirements for Plasma Modeling
The Data Required for Plasma Modeling chapter describes the Data Requirements to model low-temperature plasmas. It gives an overview of the data you need to assemble before attempting to model a plasma. It also includes the section Importing Collision Cross-Section Data.
AC/DC Interfaces
AC/DC Interfaces chapter describes the two physics interfaces available with this module under the AC/DC branch when adding a physics interface. This module enhances the physics interface included with the basic COMSOL Multiphysics license. Use the Electrical Circuit interface to add an external electrical circuit to the plasma model. Also see The Magnetic Fields Interface in the COMSOL Multiphysics Reference Manual for information about this physics interface and its feature node settings.
Fluid Flow Interfaces
Fluid Flow Interface describes the Laminar Flow interface, which has a few additional features available for this module.
Boltzmann Equation, Two-Term Approximation Interface
The Boltzmann Equation, Two-Term Approximation Interface chapter describes the physics interface, which computes the electron energy distribution function (EEDF) from a set of collision cross sections for some mean discharge conditions. Additionally, electron source coefficients and transport properties can be computed.
Drift Diffusion Interface
The Drift Diffusion Interface chapter describes the underlying electron transport theory for the Drift Diffusion interface and details the available features. Use the Drift Diffusion interface to compute the electron density and mean electron energy. A wide range of boundary conditions are available to handle secondary emission, thermionic emission, and wall losses.
The Heavy Species Interface
The Heavy Species Transport Interface chapter describes the physics interface, which is a mass balance interface for all nonelectron species. This includes charged, neutral, and excited species. The physics interface also allows you to add electron impact reactions, chemical reactions, surface reactions, and species via the Model Builder.
The Plasma Interfaces
Plasma Interfaces chapter describes the following multiphysics interfaces.
The Plasma Interface can be used to study discharges that are sustained by time-varying electrostatic fields or static electric fields. Rate or Townsend coefficients can be used to define the collisional processes occurring in the plasma. When rate coefficients are used, cross section data can be imported, and the rate coefficient will be automatically computed.
The Plasma, Time Periodic Interface is used for discharges sustained by a periodic excitation, as is found in capacitively coupled plasmas. The applied frequency should typically be in the MHz range.
The Inductively Coupled Plasma Interface is for studying discharges that are sustained by induction currents. The induction currents are solved for in the frequency domain and all other variables in the time domain. The electron heating due to the induction currents is handled automatically using multiphysics features. The 3D components require the AC/DC Module.
The Inductively Coupled Plasma with RF Bias Interface is for studying discharges that are sustained by induction currents and have a periodic RF-biased electrode.
The Microwave Plasma Interface requires the RF Module, and is used to study discharges that are sustained by electromagnetic waves (wave-heated discharge). Heating of the electrons due to their interaction with the electromagnetic waves is handled automatically using multiphysics features. The electromagnetic equations are solved in the frequency domain.
The Equilibrium Discharges Interfaces
Equilibrium Discharges Interfaces chapter describes physics interfaces that can be used to model plasma in or in close local thermodynamic equilibrium (LTE), that is, where the electrons and heavy particles temperature are approximately equal.
The Electric discharges Interfaces
The Electrical Breakdown Detection Interface uses an approximate method to determine if electric breakdown occurs in a given system by integrating Townsend coefficients along electric field lines.
The Corona Discharge Interface uses a simplified charge transport model coupled with electrostatics to provide an approximate method of computing the charge density and the electrostatic potential in corona discharges.