Study and Study Step Types

The main study step types — most of them available as a study in the window — are listed in Table 20-2. Some studies require add-on modules, and these are listed in Table 20-3 (in that list, the submenu under in the branches appears in parentheses for the study types that are available as individual study steps).

Also see Study Extension Steps and Advanced Study Extension Steps for additional information about some study steps that do not generate equations and which can only be used in combination with other study steps. In Table 20-2, these are listed as supplemental studies and study steps.

Table 20-2: Standard Study types, Study Steps, and Study Extension Steps
Icon	Study or Study Step	Brief Description
	Empty Study	An Empty Study creates a Study node with no study steps.
	General Studies	Studies that are generally available, such as Stationary and Time Dependent.
	Preset Studies/Preset Studies for Selected Physics Interfaces	If you have added a single-physics interface, you find suggested studies under this node. If you have added multiple physics interfaces, you find studies applicable to all physics interfaces that you have added.
	More Studies	This branch contains study types for which the selected physics interfaces are not automatically adapted. Instead, these physics interfaces have to be adapted manually using the Model Builder.
	Preset Studies for Some Physics Interfaces	Under this node, studies applicable to all physics interfaces that you have chosen to solve for appear.
	Preset Studies for Selected Multiphysics	Under this node, studies applicable to the multiphysics couplings that you have chosen to solve for appear.
	Suggested by Some Physics Interfaces	Under this node (under Preset Studies for Selected Physics Interfaces), study types common to more than one physics interface appear if you have added more than two physics interfaces.
	Name of physics interface	Under a node with the name of a physics interface under Preset Studies for Selected Physics Interfaces, study types specific to that physics interface appears.
Stationary Studies and Study Steps
	Stationary	For a stationary or steady-state situation where you can use a stationary solver. This study type is also used for optimization problems that are constrained with a stationary PDE. Adds a Stationary study step. You can also choose to create a parametric continuation solver.
Time-Dependent Studies and Study Steps
	Time Dependent	For a time-dependent or transient simulation using a Time-Dependent Solver for computing the solution over time. This study type is also used for optimization problems that are constrained with a time-dependent PDE. Adds a Time Dependent study step.
	Time Discrete	Only available as a Time Dependent study step. Use it to perform time-dependent analysis using the projection method.
	Frequency to Time FFT	This study step performs an FFT (or nonuniform Fourier transform) from the frequency domain (the input) to the time domain for a time-dependent study.
Eigenfrequency Studies and Study Steps
	Eigenfrequency	This study is similar to an Eigenvalue study but computes the eigenfrequencies instead of the eigenvalues. Adds an Eigenfrequency study step.
	Eigenvalue	This study uses a formulation to compute eigenvalues and eigenmodes using an eigenvalue solver. Adds an Eigenvalue study step.
Frequency Domain Studies and Study Steps
	Frequency Domain	For a study in the frequency domain such as wave equations or frequency response analysis. Adds a Frequency Domain study step.
	Frequency Domain Perturbation	Use this study step for studies of small oscillations about a bias solution. This study step follows a study step that computes the stationary (or bias) solution and computes a perturbed solution of the linearized problem around the linearization point (or bias point) computed in the first step.
	Time to Frequency FFT	This study step performs an FFT from the time domain (the input) to the frequency domain (output) for a frequency-domain study.
Study Extensions Steps
	Batch	Use this step to start a COMSOL Multiphysics batch process that solves the current study on your computer.
	Batch Sweep	Use this step to find the solution to a sequence of stationary or time-dependent simulations that arise when you vary some parameters of interest.
	Cluster Computing	Use this step when you want to submit COMSOL Multiphysics batch jobs to a job scheduler that in turn runs the batch job on a second computer or cluster.
	Cluster Sweep	Use this step to find the solution to a sequence of stationary or time-dependent simulations that arise when you vary some parameters of interest.
	Combine Solutions	Use this step to combine two solutions; for example, two time-dependent simulations over two different time spans that you want to postprocess as a single time-dependent solution.
	Function Sweep	This is a special case of Parametric Sweep study step, where the solver sweeps over functions defined under a Switch node defined under Global Definitions>Functions.
	Material Sweep	This is a special case of Parametric Sweep, where the solver sweeps over materials defined under a Switch node defined under Materials.
	Model Reduction	Use this step to create a reduced-order model from a time-dependent or frequency-domain simulation.
	Multigrid Level	This can be added as a subnode to other study step nodes to describe a geometric multigrid level used by the study.
	Parametric Sweep	Use this step to find the solution to a sequence of stationary or time-dependent problems that arise when you vary some parameters of interest. Add to a study to perform a parametric variation on other studies.
	Sensitivity	Use this step to add a sensitivity analysis to the study. Using a Sensitivity study node you can add sensitivity functions at the study level and use model parameters as global control variables.
	Study Reference	Use this step to refer to another study in the model.

Table 20-2: Standard Study types, Study Steps, and Study Extension Steps

An Empty Study creates a Study node with no study steps.

General Studies

Studies that are generally available, such as Stationary and Time Dependent.

Preset Studies/Preset Studies for Selected Physics Interfaces

If you have added a single-physics interface, you find suggested studies under this node.

If you have added multiple physics interfaces, you find studies applicable to all physics interfaces that you have added.

More Studies

This branch contains study types for which the selected physics interfaces are not automatically adapted. Instead, these physics interfaces have to be adapted manually using the Model Builder.

Preset Studies for Some Physics Interfaces

Under this node, studies applicable to all physics interfaces that you have chosen to solve for appear.

Preset Studies for Selected Multiphysics

Under this node, studies applicable to the multiphysics couplings that you have chosen to solve for appear.

Suggested by Some Physics Interfaces

Under this node (under Preset Studies for Selected Physics Interfaces), study types common to more than one physics interface appear if you have added more than two physics interfaces.

Name of physics interface

Under a node with the name of a physics interface under Preset Studies for Selected Physics Interfaces, study types specific to that physics interface appears.

Stationary Studies and Study Steps

Stationary

For a stationary or steady-state situation where you can use a stationary solver. This study type is also used for optimization problems that are constrained with a stationary PDE. Adds a Stationary study step. You can also choose to create a parametric continuation solver.

Time-Dependent Studies and Study Steps

Time Dependent

For a time-dependent or transient simulation using a Time-Dependent Solver for computing the solution over time. This study type is also used for optimization problems that are constrained with a time-dependent PDE. Adds a Time Dependent study step.

Time Discrete

Only available as a Time Dependent study step. Use it to perform time-dependent analysis using the projection method.

Frequency to Time FFT

This study step performs an FFT (or nonuniform Fourier transform) from the frequency domain (the input) to the time domain for a time-dependent study.

Eigenfrequency Studies and Study Steps

Eigenfrequency

This study is similar to an Eigenvalue study but computes the eigenfrequencies instead of the eigenvalues. Adds an Eigenfrequency study step.

Eigenvalue

This study uses a formulation to compute eigenvalues and eigenmodes using an eigenvalue solver. Adds an Eigenvalue study step.

Frequency Domain Studies and Study Steps

Frequency Domain

For a study in the frequency domain such as wave equations or frequency response analysis. Adds a Frequency Domain study step.

Frequency Domain Perturbation

Use this study step for studies of small oscillations about a bias solution. This study step follows a study step that computes the stationary (or bias) solution and computes a perturbed solution of the linearized problem around the linearization point (or bias point) computed in the first step.

Time to Frequency FFT

This study step performs an FFT from the time domain (the input) to the frequency domain (output) for a frequency-domain study.

Study Extensions Steps

Batch

Use this step to start a COMSOL Multiphysics batch process that solves the current study on your computer.

Batch Sweep

Use this step to find the solution to a sequence of stationary or time-dependent simulations that arise when you vary some parameters of interest.

Cluster Computing

Use this step when you want to submit COMSOL Multiphysics batch jobs to a job scheduler that in turn runs the batch job on a second computer or cluster.

Cluster Sweep

Use this step to find the solution to a sequence of stationary or time-dependent simulations that arise when you vary some parameters of interest.

Combine Solutions

Use this step to combine two solutions; for example, two time-dependent simulations over two different time spans that you want to postprocess as a single time-dependent solution.

Function Sweep

This is a special case of Parametric Sweep study step, where the solver sweeps over functions defined under a Switch node defined under Global Definitions>Functions.

Material Sweep

This is a special case of Parametric Sweep, where the solver sweeps over materials defined under a Switch node defined under Materials.

Model Reduction

Use this step to create a reduced-order model from a time-dependent or frequency-domain simulation.

Multigrid Level

This can be added as a subnode to other study step nodes to describe a geometric multigrid level used by the study.

Parametric Sweep

Use this step to find the solution to a sequence of stationary or time-dependent problems that arise when you vary some parameters of interest. Add to a study to perform a parametric variation on other studies.

Sensitivity

Use this step to add a sensitivity analysis to the study. Using a Sensitivity study node you can add sensitivity functions at the study level and use model parameters as global control variables.

Study Reference

Use this step to refer to another study in the model.

Table 20-3: Studies and Study Steps Available with Add-on Modules
Icon	Study or Study Step	Description	Required Module
Chemical Applications
	AC Impedance, Initial Values	The AC Impedance Initial Values study is used for electrochemical impedance spectroscopy (EIS) computations in electrochemical cells. The study consists of a single Frequency Domain Perturbation study step, which solves for a harmonic linear perturbation.	Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module
	AC Impedance, Stationary	Two study steps solve for a stationary problem and a harmonic perturbation in the frequency domain of the stationary solution.	Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module
	AC Impedance, Time Dependent	Two study steps solve for a time-dependent problem and a harmonic perturbation in the frequency domain of the solution at the last time step.	Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module
	Cyclic Voltammetry (under Time Dependent)	This study uses the Electroanalysis interface to perform transient simulations of voltammetry experiments.	Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module
	Stationary Plug Flow (under Stationary)	This study is used for plug flow reactor models created with the Reaction Engineering interface. It is used to solve for the molar flow rate as a function of reactor volume.	Chemical Reaction Engineering Module
	Time-Dependent with Initialization	Use this study to perform transient simulations of electrochemical cells. It solves for the electrode and electrolyte potentials as well as all global ODE dependent variables. It also performs a transient simulation for all dependent variables in the model, using the result of the first study step as initial values.	Corrosion Module or Electrodeposition Module
	Time Dependent, Fixed Geometry	Use this study to exclude geometry deformation effects from a model. The study is similar to the Time-Dependent with Initialization study.	Corrosion Module or Electrodeposition Module
Electrical and Optical Applications
	Bidirectionally Coupled Particle Tracing	This study is used to model the interactions of particle or ray trajectories with stationary fields. The study creates a Time Dependent solver that solves for all degrees of freedom related to the particles or rays. All other degrees of freedom are computed using a Stationary solver. The two solvers are repeated using a For-End For loop so that a self-consistent solution is obtained, taking the bidirectional coupling between the moving particles or rays and stationary fields into account.	Particle Tracing Module
	Bidirectionally Coupled Ray Tracing	This study is used to compute ray trajectories that are affected by external fields. This study solves for all degrees of freedom related to rays using a Time-Dependent solver. All other degrees of freedom are computed using a Stationary solver. The two solvers are repeated using a For-End For loop so that a self-consistent solution is obtained, taking the bidirectional coupling between the propagating rays and stationary fields into account.	Ray Optics Module
	Boundary Mode Analysis	Combines a mode analysis on a port (boundary) with a frequency domain study for the full geometry. Adds a Boundary Mode Analysis study step followed by a Frequency Domain study step.	RF Module or Wave Optics Module
	Coil Geometry Analysis	Use this study to solve an eigenvalue problem for the current flow in a Multiturn Coil Domain node that gives the current density likely produced by a bundle of conductive wires.	AC/DC Module
	Time to Frequency Losses	Use this study to compute the losses in a Loss Calculation Domain subnode where the loss model is set to Steinmetz or Bertotti. This study step performs an FFT from the time domain (the input) to the frequency domain that is used to compute the losses (output) based on empirical formulas or the time integral of resistive heating.	AC/DC Module
	Frequency-Stationary	This is a special case of a Stationary study and is available with the Induction Heating, Microwave Heating, and Laser Heating interfaces.	AC/DC Module, Plasma Module, RF Module, or Wave Optics Module
	Frequency-Transient	Compute electromagnetic fields in the frequency domain and the temperature (or electron temperature) in the time domain. Available with the Induction Heating, Microwave Heating, Inductively Coupled Plasma, and Microwave Plasma interfaces.	AC/DC Module, Plasma Module, RF Module, or Wave Optics Module
	Mean Energies (under Frequency Domain)	Use this study to enter an array of values for the mean electron energy. Available with the Boltzmann Equation, Two-Term Approximation interface.	Plasma Module
	Ray Tracing	Computes the trajectories of rays. This is a special case of the Time Dependent study step. The time list can either be specified directly or by entering a list of lengths and a characteristic group velocity. Built-in stop conditions can be used to stop the solver when no active rays remain, or when the intensity of active rays is negligibly small.	Ray Optics Module or Acoustics Module
	Reduced Electric Fields (under Frequency Domain)	Use this study to sweep through a range of reduced electric fields. Available with the Boltzmann Equation, Two-Term Approximation interface.	Plasma Module
	Schrödinger-Poisson	Use this study for the self consistent solution to the Schrödinger-Poisson system.	Semiconductor Module
	Semiconductor Equilibrium	Use it to solve Poisson’s equation for the case where the charge carriers are in thermal equilibrium.	Semiconductor Module
	Semiconductor Initialization	Use it to adaptively refine the mesh based on the gradient of the impurity doping concentration.	Semiconductor Module
	Frequency-Stationary, One-Way Electromagnetic Heating	First solve a frequency-domain equation for electromagnetics and then use the electromagnetic heat source as a source term when solving a subsequent stationary heat transfer equation. Available with the Induction Heating, Microwave Heating, or Laser Heating interfaces.	AC/DC Module, RF Module, or Wave Optics Module
	Frequency-Transient, One-Way Electromagnetic Heating	Sequentially compute electromagnetic fields in the frequency domain and then the temperature (or electron temperature) in the time domain. Available with the Induction Heating, Microwave Heating, and Laser Heating interfaces.	AC/DC Module, RF Module, or Wave Optics Module
	Frequency Domain, RF Adaptive Mesh	Solve a frequency-domain study that runs mesh adaptation for printed circuit boards and RF applications.	RF Module
	Frequency Domain Source Sweep	Solve a frequency-domain study that is sweeping among feedings such as ports and lumped ports, extracting automatically a full S-parameter matrix.	RF Module or Wave Optics Module
	Stationary Source Sweep	A stationary source sweep to extract lumped matrices such as a capacity matrix in Electrostatics.	AC/DC Module
	Stationary Source Sweep with Initialization	A combination of the source initialization study step and the stationary source sweep study step to extract lumped matrices such as a inductance matrix in Magnetic Fields, Currents Only.	AC/DC Module
	Frequency Domain Source Sweep with Initialization	A combination of the source initialization study step and the frequency domain source sweep study step to extract lumped matrices such as a inductance matrix in Magnetic Fields, Currents Only.	AC/DC Module
	TEM Boundary Mode Analysis	Combines a frequency-domain analysis on port features (boundaries) with a frequency domain study for the full geometry. Adds a TEM Boundary Mode Analysis study step followed by a Frequency Domain study step.	RF Module
	Time Dependent, Modal	This study is for analyzing time-dependent wave problems using a modal solver. The Time Dependent, Modal study adds an Eigenfrequency study step followed by a Time Dependent, Modal study step.	RF Module, Acoustics Module, MEMS Module, Structural Mechanics Module, or Wave Optics Module
	EEDF Initialization	The EEDF Initialization study is used to compute the electron energy distribution function (EEDF) without solving for the other plasma degrees of freedom. It can also be used to compute the initial EEDF for a time and space dependent plasma model.	Plasma Module
	Time Periodic	This study solves for the periodic steady-state solution in model using the Plasma, Time Periodic interface.	Plasma Module
	Time Periodic to Time Dependent	This study converts a time-periodic solution to a time-dependent solution in a model using the Plasma, Time Periodic interface.	Plasma Module
	Wavelength Domain	Use this study to compute the response of a linear or linearized model subjected to electromagnetic harmonic excitation for one or several wavelengths.	Wave Optics Module
Fluid Applications
	Frozen Rotor	This is a special case of a Stationary study. The frozen rotor approach assumes that the flow in the rotating domain, expressed in the rotating coordinate system, is fully developed. Available with the Rotating Machinery, Laminar Flow, and Turbulent Flow interfaces.	CFD Module or Mixer Module
	Frozen Rotor with Initialization	For flow in rotating machinery where the topology of the geometry does not change with rotation. You can also use it to compute the initial conditions for time-dependent simulations of flow in rotating machinery.	CFD Module or Mixer Module
	Stationary Free Surface	A study step added to a Frozen Rotor or Frozen Rotor with Initialization study to solve for the free surface deformation.	CFD Module
	Frozen Rotor with Stationary Free Surface	Two study steps, a Frozen Rotor solving for the fluid flow variables and a Stationary Free Surface one solving for the free surface deformation. Available with the Rotating Machinery, Laminar Flow, and Turbulent Flow interfaces.	CFD Module or Mixer Module
	Frozen Rotor with Initialization and Stationary Free Surface	Three study steps, a Wall Distance Initialization, followed by a Frozen Rotor solving for the fluid flow variables and a Stationary Free Surface one solving for the free surface deformation. Available with the Rotating Machinery, Turbulent Flow interfaces.	CFD Module or Mixer Module
	Stationary with Initialization	For stationary turbulent flow models that require an initialization.	CFD Module or Heat Transfer Module
	Time Dependent with Initialization	For time-dependent turbulent flow models that require an initialization.	CFD Module or Heat Transfer Module
	Thermal Perturbation, Eigenfrequency	For computing the oscillations around an equilibrium steady-state temperature field using: a Stationary study step followed by an Eigenfrequency study step.	Heat Transfer Module
	Thermal Perturbation, Frequency Domain	For computing the oscillations around an equilibrium steady-state temperature field using: a Stationary study step followed by a Frequency-Domain, Perturbation study step.	Heat Transfer Module
	Time Dependent with Phase Initialization	For time-dependent two-phase flow models that require an initialization of a level set function or phase field function.	CFD Module or Microfluidics Module
	Stationary, One-Way NITF	Two stationary study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.	CFD Module or Heat Transfer Module
	Time Dependent, One-Way NITF	Two time-dependent study steps, one solving for the fluid flow variables and one solving for the heat transfer variables in the time domain. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.	CFD Module or Heat Transfer Module
	Frozen Rotor, One-Way NITF	Two frozen rotor study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Rotating Machinery, Nonisothermal Flow interfaces.	Mixer Module plus CFD Module
	Stationary, One-Way with Initialization NITF	A wall distance initialization followed by two stationary study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.	CFD Module or Heat Transfer Module
	Time Dependent, One-Way with Initialization NITF	A wall distance initialization followed by two time dependent study steps, one solving for the fluid flow variables and one solving for the heat transfer variables in the time domain. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.	CFD Module or Heat Transfer Module
	Frozen Rotor, One-Way with Initialization NITF	Two frozen rotor study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Rotating Machinery, Nonisothermal Flow interfaces.	Mixer Module plus CFD Module
	Stationary, One-Way MF	Two study steps, one solving for the fluid flow variables and one solving for the moisture transport variables. Available with the Moisture Flow interface.	Heat Transfer Module
	Time Dependent, One-Way MF	Two study steps, one solving for the fluid flow variables and one solving for the moisture transport variables in the time domain. Available with the Moisture Flow interface.	Heat Transfer Module
Mechanical and Acoustic Applications
	Bolt Pretension	This study step is a special case of a Stationary study step, where the special degrees of freedoms used for modeling prestressed bolts are solved for.	Structural Mechanics Module
	Fatigue	Use this study for fatigue evaluation. It processes a load cycle and evaluates a fatigue criterion specified in the Fatigue interface.	Structural Mechanics Module plus Fatigue Module
	Linear Buckling	Use this study for a structural model to solve for the critical load factor using an eigenvalue solver.	Structural Mechanics Module or MEMS Module
	Eigenfrequency, Prestressed	For computing eigenfrequencies that are influenced by a prior static load.	Structural Mechanics Module, Geomechanics Module, MEMS Module, or Acoustics Module
	Frequency Domain, Prestressed	For computing the response to harmonic loads fluctuating around a static preload.
	Frequency Domain, Prestressed, Modal	Three study steps are used to compute the response to harmonic loads fluctuating around a prior static load. The solution is performed using mode superposition.	Structural Mechanics Module, Acoustics Module, or MEMS Module
	Random Vibration (PSD)	Adds three studies and a number of nodes under Global Definitions for a random vibration analysis.	Structural Mechanics Module or MEMS Module
	Response Spectrum	Adds a Response Spectrum node under Definitions and an Eigenfrequency study step for a response-spectrum analysis.	Structural Mechanics Module or MEMS Module
	Time Dependent, Prestressed, Modal	Three study steps are used to compute the response to time-dependent loads fluctuating around a prior static load. The solution is performed using mode superposition.	Structural Mechanics Module, Acoustics Module, or MEMS Module
	Stationary, One Way	Two study steps solve for the fluid flow variables and for the solid deformation. Available with the Fluid-Structure Interaction interface.	MEMS Module or Structural Mechanics Module
	Time Dependent, One Way	Two study steps solve for the fluid flow variables and for the solid deformation in the time domain. Available with the Fluid-Structure Interaction interface.
	Stationary, One Way with Initialization	Three study steps solve for the distance to the closest wall, for the fluid flow variables, and for the solid deformation. Available with the Fluid-Structure Interaction interface.	MEMS Module or Structural Mechanics Module, plus the CFD Module
	Time Dependent, One Way with Initialization	Three study steps solve for the distance to the closest wall, for the fluid flow variables, and for the solid deformation in the time domain. Available with the Fluid-Structure Interaction interface.
	Time Dependent with FFT	Two study steps for computing a time-dependent solution using a Time Dependent study step and then applying a Time to Frequency FFT study step. Available with the Solid Rotor and Beam Rotor interfaces.	Rotordynamics Module
	Mapping	A dedicated study for the Background Fluid Flow Coupling multiphysics feature.	Acoustics Module
	Transient Mapping	A dedicated study for the Aeroacoustic Flow Source Coupling multiphysics feature.	Acoustics Module
Multipurpose Applications
	Adaptive Frequency Sweep	The Adaptive Frequency Sweep study is for analyzing the frequency response of a linear or linearized model subjected to harmonic excitation in the frequency domain using an AWE solver.	MEMS Module, RF Module, or Wave Optics Module
	Frequency Domain, Modal	The Frequency Domain, Modal study is for analyzing wave problems in the frequency domain using a modal solver. It adds an Eigenfrequency study step followed by a Frequency Domain, Modal study step.	Structural Mechanics Module, MEMS Module, Acoustics Module, RF Module, or Wave Optics Module
	Mode Analysis	Computes the modes for an acoustic or electromagnetic wave using an eigenvalue solver.	Acoustics Module, RF Module, or Wave Optics Module
	Modal Reduced-Order Model	You can add a Modal Reduced-Order Model study step to export the reduced-order model matrices for time-dependent wave problems using a modal solver. Available from the Study node under Study Steps>Time dependent.	Structural Mechanics Module, MEMS Module, Acoustics Module, RF Module, or Wave Optics Module
	Frequency Domain, AWE Reduced-Order Model	The Frequency Domain, AWE Reduced-Order Model is an entry point which creates studies and other features which facilitates the setup of reduced-order models for frequency domain analysis using the AWE method.	Structural Mechanics Module, MEMS Module, Acoustics Module
	Frequency Domain, Modal Reduced-Order Model	The Frequency Domain, Modal Reduced-Order Model is an entry point which creates studies and other features which facilitates the setup of reduced-order models for frequency domain analysis using mode superposition.	Structural Mechanics Module, MEMS Module, Acoustics Module
	Time Dependent, Modal Reduced-Order Model	The Time Dependent, Modal Reduced-Order Model is an entry point which creates studies and other features which facilitates the setup of reduced-order models for time domain analysis using mode superposition.	Structural Mechanics Module, MEMS Module, Acoustics Module,
	Optimization	Use this study to solve PDE-constrained optimization problems. This study step allows direct definition of objective functions and selection of model parameters, including parameters that control the geometry, for optimization. It also provides detailed control over solvers and contributions to an optimization problem defined by an Optimization interface.	Optimization Module
	Curve Fitting	This study provides parameter estimation for time-dependent models.	Optimization Module
	Shape Optimization	Use this study to perform shape optimization.	Optimization Module
	Topology Optimization	Use this study to perform topology optimization.	Optimization Module
	Parameter Estimation	This study provides parameter estimation for all types of models.	Optimization Module
	Uncertainty Quantification	Add an uncertainty quantification study type.	Uncertainty Quantification Module.
	Small-Signal Analysis, Frequency Domain	For perturbed frequency domain studies of small oscillation about a bias solution. The study creates two study steps that solve for a stationary problem and for a harmonic perturbation in the frequency domain of the stationary solution.	AC/DC Module, MEMS Module, or Semiconductor Module

Table 20-3: Studies and Study Steps Available with Add-on Modules

Chemical Applications

AC Impedance, Initial Values

The AC Impedance Initial Values study is used for electrochemical impedance spectroscopy (EIS) computations in electrochemical cells.

The study consists of a single Frequency Domain Perturbation study step, which solves for a harmonic linear perturbation.

Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module

AC Impedance, Stationary

Two study steps solve for a stationary problem and a harmonic perturbation in the frequency domain of the stationary solution.

Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module

AC Impedance, Time Dependent

Two study steps solve for a time-dependent problem and a harmonic perturbation in the frequency domain of the solution at the last time step.

Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module

Cyclic Voltammetry (under Time Dependent)

This study uses the Electroanalysis interface to perform transient simulations of voltammetry experiments.

Battery Design Module, Corrosion Module, Electrochemistry Module, or Electrodeposition Module

Stationary Plug Flow (under Stationary)

This study is used for plug flow reactor models created with the Reaction Engineering interface. It is used to solve for the molar flow rate as a function of reactor volume.

Chemical Reaction Engineering Module

Time-Dependent with Initialization

Use this study to perform transient simulations of electrochemical cells. It solves for the electrode and electrolyte potentials as well as all global ODE dependent variables. It also performs a transient simulation for all dependent variables in the model, using the result of the first study step as initial values.

Corrosion Module or Electrodeposition Module

Time Dependent, Fixed Geometry

Use this study to exclude geometry deformation effects from a model. The study is similar to the Time-Dependent with Initialization study.

Corrosion Module or Electrodeposition Module

Electrical and Optical Applications

Bidirectionally Coupled Particle Tracing

This study is used to model the interactions of particle or ray trajectories with stationary fields. The study creates a Time Dependent solver that solves for all degrees of freedom related to the particles or rays. All other degrees of freedom are computed using a Stationary solver. The two solvers are repeated using a For-End For loop so that a self-consistent solution is obtained, taking the bidirectional coupling between the moving particles or rays and stationary fields into account.

Particle Tracing Module

Bidirectionally Coupled Ray Tracing

This study is used to compute ray trajectories that are affected by external fields. This study solves for all degrees of freedom related to rays using a Time-Dependent solver. All other degrees of freedom are computed using a Stationary solver. The two solvers are repeated using a For-End For loop so that a self-consistent solution is obtained, taking the bidirectional coupling between the propagating rays and stationary fields into account.

Ray Optics Module

Boundary Mode Analysis

Combines a mode analysis on a port (boundary) with a frequency domain study for the full geometry. Adds a Boundary Mode Analysis study step followed by a Frequency Domain study step.

RF Module or Wave Optics Module

Coil Geometry Analysis

Use this study to solve an eigenvalue problem for the current flow in a Multiturn Coil Domain node that gives the current density likely produced by a bundle of conductive wires.

AC/DC Module

Time to Frequency Losses

Use this study to compute the losses in a Loss Calculation Domain subnode where the loss model is set to Steinmetz or Bertotti. This study step performs an FFT from the time domain (the input) to the frequency domain that is used to compute the losses (output) based on empirical formulas or the time integral of resistive heating.

AC/DC Module

Frequency-Stationary

This is a special case of a Stationary study and is available with the Induction Heating, Microwave Heating, and Laser Heating interfaces.

AC/DC Module, Plasma Module, RF Module, or Wave Optics Module

Frequency-Transient

Compute electromagnetic fields in the frequency domain and the temperature (or electron temperature) in the time domain. Available with the Induction Heating, Microwave Heating, Inductively Coupled Plasma, and Microwave Plasma interfaces.

AC/DC Module, Plasma Module, RF Module, or Wave Optics Module

Mean Energies (under Frequency Domain)

Use this study to enter an array of values for the mean electron energy. Available with the Boltzmann Equation, Two-Term Approximation interface.

Plasma Module

Ray Tracing

Computes the trajectories of rays. This is a special case of the Time Dependent study step. The time list can either be specified directly or by entering a list of lengths and a characteristic group velocity. Built-in stop conditions can be used to stop the solver when no active rays remain, or when the intensity of active rays is negligibly small.

Ray Optics Module or Acoustics Module

Reduced Electric Fields (under Frequency Domain)

Use this study to sweep through a range of reduced electric fields. Available with the Boltzmann Equation, Two-Term Approximation interface.

Plasma Module

Schrödinger-Poisson

Use this study for the self consistent solution to the Schrödinger-Poisson system.

Semiconductor Module

Semiconductor Equilibrium

Use it to solve Poisson’s equation for the case where the charge carriers are in thermal equilibrium.

Semiconductor Module

Semiconductor Initialization

Use it to adaptively refine the mesh based on the gradient of the impurity doping concentration.

Semiconductor Module

Frequency-Stationary, One-Way Electromagnetic Heating

First solve a frequency-domain equation for electromagnetics and then use the electromagnetic heat source as a source term when solving a subsequent stationary heat transfer equation. Available with the Induction Heating, Microwave Heating, or Laser Heating interfaces.

AC/DC Module, RF Module, or Wave Optics Module

Frequency-Transient, One-Way Electromagnetic Heating

Sequentially compute electromagnetic fields in the frequency domain and then the temperature (or electron temperature) in the time domain. Available with the Induction Heating, Microwave Heating, and Laser Heating interfaces.

AC/DC Module, RF Module, or Wave Optics Module

Frequency Domain, RF Adaptive Mesh

Solve a frequency-domain study that runs mesh adaptation for printed circuit boards and RF applications.

RF Module

Frequency Domain Source Sweep

Solve a frequency-domain study that is sweeping among feedings such as ports and lumped ports, extracting automatically a full S-parameter matrix.

RF Module or Wave Optics Module

Stationary Source Sweep

A stationary source sweep to extract lumped matrices such as a capacity matrix in Electrostatics.

AC/DC Module

Stationary Source Sweep with Initialization

A combination of the source initialization study step and the stationary source sweep study step to extract lumped matrices such as a inductance matrix in Magnetic Fields, Currents Only.

AC/DC Module

Frequency Domain Source Sweep with Initialization

A combination of the source initialization study step and the frequency domain source sweep study step to extract lumped matrices such as a inductance matrix in Magnetic Fields, Currents Only.

AC/DC Module

TEM Boundary Mode Analysis

Combines a frequency-domain analysis on port features (boundaries) with a frequency domain study for the full geometry. Adds a TEM Boundary Mode Analysis study step followed by a Frequency Domain study step.

RF Module

Time Dependent, Modal

This study is for analyzing time-dependent wave problems using a modal solver. The Time Dependent, Modal study adds an Eigenfrequency study step followed by a Time Dependent, Modal study step.

RF Module, Acoustics Module, MEMS Module, Structural Mechanics Module, or Wave Optics Module

EEDF Initialization

The EEDF Initialization study is used to compute the electron energy distribution function (EEDF) without solving for the other plasma degrees of freedom. It can also be used to compute the initial EEDF for a time and space dependent plasma model.

Plasma Module

Time Periodic

This study solves for the periodic steady-state solution in model using the Plasma, Time Periodic interface.

Plasma Module

Time Periodic to Time Dependent

This study converts a time-periodic solution to a time-dependent solution in a model using the Plasma, Time Periodic interface.

Plasma Module

Wavelength Domain

Use this study to compute the response of a linear or linearized model subjected to electromagnetic harmonic excitation for one or several wavelengths.

Wave Optics Module

Fluid Applications

Frozen Rotor

This is a special case of a Stationary study. The frozen rotor approach assumes that the flow in the rotating domain, expressed in the rotating coordinate system, is fully developed. Available with the Rotating Machinery, Laminar Flow, and Turbulent Flow interfaces.

CFD Module or Mixer Module

Frozen Rotor with Initialization

For flow in rotating machinery where the topology of the geometry does not change with rotation. You can also use it to compute the initial conditions for time-dependent simulations of flow in rotating machinery.

CFD Module or Mixer Module

Stationary Free Surface

A study step added to a Frozen Rotor or Frozen Rotor with Initialization study to solve for the free surface deformation.

CFD Module

Frozen Rotor with Stationary Free Surface

Two study steps, a Frozen Rotor solving for the fluid flow variables and a Stationary Free Surface one solving for the free surface deformation. Available with the Rotating Machinery, Laminar Flow, and Turbulent Flow interfaces.

CFD Module or Mixer Module

Frozen Rotor with Initialization and Stationary Free Surface

Three study steps, a Wall Distance Initialization, followed by a Frozen Rotor solving for the fluid flow variables and a Stationary Free Surface one solving for the free surface deformation. Available with the Rotating Machinery, Turbulent Flow interfaces.

CFD Module or Mixer Module

Stationary with Initialization

For stationary turbulent flow models that require an initialization.

CFD Module or Heat Transfer Module

Time Dependent with Initialization

For time-dependent turbulent flow models that require an initialization.

CFD Module or Heat Transfer Module

Thermal Perturbation, Eigenfrequency

For computing the oscillations around an equilibrium steady-state temperature field using: a Stationary study step followed by an Eigenfrequency study step.

Heat Transfer Module

Thermal Perturbation, Frequency Domain

For computing the oscillations around an equilibrium steady-state temperature field using: a Stationary study step followed by a Frequency-Domain, Perturbation study step.

Heat Transfer Module

Time Dependent with Phase Initialization

For time-dependent two-phase flow models that require an initialization of a level set function or phase field function.

CFD Module or Microfluidics Module

Stationary, One-Way NITF

Two stationary study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.

CFD Module or Heat Transfer Module

Time Dependent, One-Way NITF

Two time-dependent study steps, one solving for the fluid flow variables and one solving for the heat transfer variables in the time domain. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.

CFD Module or Heat Transfer Module

Frozen Rotor, One-Way NITF

Two frozen rotor study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Rotating Machinery, Nonisothermal Flow interfaces.

Mixer Module plus CFD Module

Stationary, One-Way with Initialization NITF

A wall distance initialization followed by two stationary study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.

CFD Module or Heat Transfer Module

Time Dependent, One-Way with Initialization NITF

A wall distance initialization followed by two time dependent study steps, one solving for the fluid flow variables and one solving for the heat transfer variables in the time domain. Available with the Nonisothermal Flow and the Conjugate Heat Transfer interfaces.

CFD Module or Heat Transfer Module

Frozen Rotor, One-Way with Initialization NITF

Two frozen rotor study steps, one solving for the fluid flow variables and one solving for the heat transfer variables. Available with the Rotating Machinery, Nonisothermal Flow interfaces.

Mixer Module plus CFD Module

Stationary, One-Way MF

Two study steps, one solving for the fluid flow variables and one solving for the moisture transport variables. Available with the Moisture Flow interface.

Heat Transfer Module

Time Dependent, One-Way MF

Two study steps, one solving for the fluid flow variables and one solving for the moisture transport variables in the time domain. Available with the Moisture Flow interface.

Heat Transfer Module

Mechanical and Acoustic Applications

Bolt Pretension

This study step is a special case of a Stationary study step, where the special degrees of freedoms used for modeling prestressed bolts are solved for.

Structural Mechanics Module

Fatigue

Use this study for fatigue evaluation. It processes a load cycle and evaluates a fatigue criterion specified in the Fatigue interface.

Structural Mechanics Module plus Fatigue Module

Linear Buckling

Use this study for a structural model to solve for the critical load factor using an eigenvalue solver.

Structural Mechanics Module or MEMS Module

Eigenfrequency, Prestressed

For computing eigenfrequencies that are influenced by a prior static load.

Structural Mechanics Module, Geomechanics Module, MEMS Module, or Acoustics Module

Frequency Domain, Prestressed

For computing the response to harmonic loads fluctuating around a static preload.

Frequency Domain, Prestressed, Modal

Three study steps are used to compute the response to harmonic loads fluctuating around a prior static load. The solution is performed using mode superposition.

Structural Mechanics Module, Acoustics Module, or MEMS Module

Random Vibration (PSD)

Adds three studies and a number of nodes under Global Definitions for a random vibration analysis.

Structural Mechanics Module or MEMS Module

Response Spectrum

Adds a Response Spectrum node under Definitions and an Eigenfrequency study step for a response-spectrum analysis.

Structural Mechanics Module or MEMS Module

Time Dependent, Prestressed, Modal

Three study steps are used to compute the response to time-dependent loads fluctuating around a prior static load. The solution is performed using mode superposition.

Structural Mechanics Module, Acoustics Module, or MEMS Module

Stationary, One Way

Two study steps solve for the fluid flow variables and for the solid deformation. Available with the Fluid-Structure Interaction interface.

MEMS Module or Structural Mechanics Module

Time Dependent, One Way

Two study steps solve for the fluid flow variables and for the solid deformation in the time domain. Available with the Fluid-Structure Interaction interface.

Stationary, One Way with Initialization

Three study steps solve for the distance to the closest wall, for the fluid flow variables, and for the solid deformation. Available with the Fluid-Structure Interaction interface.

MEMS Module or Structural Mechanics Module, plus the CFD Module

Time Dependent, One Way with Initialization

Three study steps solve for the distance to the closest wall, for the fluid flow variables, and for the solid deformation in the time domain. Available with the Fluid-Structure Interaction interface.

Time Dependent with FFT

Two study steps for computing a time-dependent solution using a Time Dependent study step and then applying a Time to Frequency FFT study step. Available with the Solid Rotor and Beam Rotor interfaces.

Rotordynamics Module

Mapping

A dedicated study for the Background Fluid Flow Coupling multiphysics feature.

Acoustics Module

Transient Mapping

A dedicated study for the Aeroacoustic Flow Source Coupling multiphysics feature.

Acoustics Module

Multipurpose Applications

Adaptive Frequency Sweep

The Adaptive Frequency Sweep study is for analyzing the frequency response of a linear or linearized model subjected to harmonic excitation in the frequency domain using an AWE solver.

MEMS Module, RF Module, or Wave Optics Module

Frequency Domain, Modal

The Frequency Domain, Modal study is for analyzing wave problems in the frequency domain using a modal solver. It adds an Eigenfrequency study step followed by a Frequency Domain, Modal study step.

Structural Mechanics Module, MEMS Module, Acoustics Module, RF Module, or Wave Optics Module