Understand, Predict, and Optimize Engineering Designs with the COMSOL Multiphysics^® Software

Often, the key to successful engineering simulations is developing experimentally validated models that replace the use of experiments and prototypes alone, and give a deeper understanding of the studied design or process. Compared to running experimental methods or testing prototypes, modeling allows for quicker and often more efficient and accurate optimization of processes and devices.

As a user of COMSOL Multiphysics^®, you are free from the restrictive nature generally associated with simulation software and have complete control over all aspects of your model. You can also be creative in a way that is impossible or a lot harder with traditional approaches, thanks to the ability to couple any number of physics phenomena together and input user-defined physics descriptions, with associated equations and expressions, directly in the graphical user interface (GUI).

Accurate multiphysics models consider a wide range of possible operating conditions and physical effects. This makes it possible to use models for understanding, designing, and optimizing processes and devices for realistic operating conditions.

Modeling with COMSOL Multiphysics^® means being able to move between simulating electromagnetics, structural mechanics, acoustics, fluid flow, heat transfer, and chemical reactions phenomena, or any other physics modeled by a system of PDEs, in one software environment. You can also combine physics phenomena from these areas in a single model. The COMSOL Desktop^® user interface provides you with a complete simulation environment and a consistent modeling workflow from start to finish, regardless of the type of design or process you wish to analyze and develop.

Operations, Sequences, and Selections

The core COMSOL Multiphysics^® package provides geometry modeling tools for creating parts using solid objects, surfaces, curves, and Boolean operations. Geometries are defined by sequences of operations, where each operation is able to receive input parameters for easy edits and parametric studies in multiphysics models. The connection between the geometry definition and defined physics settings is fully associative — a change in the geometry will automatically propagate related changes throughout the associated model settings.

Geometric entities such as material domains and surfaces can be grouped into selections for subsequent use in physics definitions, meshing, and plotting. Additionally, a sequence of operations can be used to create a parametric geometry part, including its selections, which can then be stored in a Part Library for reuse in multiple models.

Import, Repair, Defeature, and Virtual Operations

The import of all standard CAD and ECAD files into COMSOL Multiphysics^® is supported by the CAD Import Module and ECAD Import Module, respectively. The Design Module further extends the available geometry operations in COMSOL Multiphysics^®. Both the CAD Import Module and the Design Module provide the ability to repair and defeature geometries. Surface mesh models, such as in the STL format, can also be imported and then converted to a geometry object by the COMSOL Multiphysics^® core package. Import operations are like any other operation in the geometry sequence and can be used with selections and associativity for performing parametric and optimization studies.

As an alternative to the defeature and repair capabilities of the COMSOL^® software, so-called virtual operations are also supported to eliminate the impact of artifacts on the mesh, such as sliver and small faces, which do not add to the accuracy of the simulation. In converse to defeaturing, virtual operations do not change the curvature or fidelity of the geometry, while yielding a cleaner mesh.

View a list of geometry modeling features

The COMSOL^® software contains predefined physics interfaces for modeling a wide range of physics phenomena, including many common multiphysics couplings. The physics interfaces are dedicated user interfaces for a particular scientific or engineering field, where all aspects for modeling the phenomena in question are made available for manipulation — from defining the model parameters to discretization to analyzing the results of the solution.

Upon selecting a particular physics interface, the software suggests available study types, such as time-dependent or stationary solvers. The software also automatically recommends the appropriate numerical discretization of the mathematical model, solver sequence, and visualization and postprocessing settings that are specific to the physics phenomena. The physics interfaces can also be combined freely in order to describe processes that involve multiple physics phenomena.

The COMSOL Multiphysics^® platform is preloaded with a large set of core physics interfaces for fields such as solid mechanics, acoustics, fluid flow, heat transfer, chemical species transport, and electromagnetics. By expanding the core package with add-on modules from the COMSOL^® product suite, you unlock a range of more specialized user interfaces that expand modeling capabilities within specific engineering fields.

View a list of physics-based modeling features

To really be useful for scientific and engineering studies and innovation, a software has to allow for more than just a hardwired environment. It should be possible to provide and customize your own model definitions based on mathematical equations directly in the user interface. The COMSOL Multiphysics^® software offers this level of flexibility with its built-in equation interpreter that can interpret expressions, equations, and other mathematical descriptions on the fly before it generates the numerical model. Adding and customizing expressions in the physics interfaces allows for freely coupling them with each other to simulate multiphysics phenomena.

The capabilities for customization go even further. With the Physics Builder, you can also use your own equations to create new physics interfaces for easy access and manipulation when you want to include them in future models or share them with colleagues.

View a list of equation-based modeling features

For discretizing and meshing your model, the COMSOL Multiphysics^® software uses different numerical techniques depending on the type of physics, or the combination of physics, that you are studying. The predominant discretization methods are finite-element based (for a complete list of methods, see the solvers section of this page). Accordingly, the general-purpose meshing algorithm creates a mesh with appropriate element types to match the associated numerical methods. For example, the default algorithm may use free tetrahedral meshing or a combination of tetrahedral and boundary-layer meshing, with a combination of element types, in order to provide faster and more accurate results.

For all of the mesh types, mesh refinement, remeshing, or adaptive meshing can be performed during the solution process or study step sequence.

View a list of meshing features

Study or Analysis Types

When you select a physics interface, a number of different studies (analysis types) are suggested by COMSOL Multiphysics^®. For example, for solid mechanics analyses, the software suggests time-dependent, stationary, or eigenfrequency studies; for CFD problems, the software would only suggest time-dependent and stationary studies. Other study types can also be freely selected for any analysis that you perform. Study step sequences structure the solution process to allow you to select the model variables for which you want to solve in each study step. The solution from any of the previous study steps can be used as input to a subsequent study step.

Sweeps, Optimization, and Estimations

Any study step can be run with a parametric sweep, which can include one or multiple parameters in a model, from geometry parameters to settings in the physics definitions. Sweeps can also be performed using different materials and their defined properties, as well as over lists of defined functions.

Optimization studies, using the Optimization Module, can be performed for topology optimization, shape optimization, or parameter estimations based on a multiphysics model. COMSOL Multiphysics^® offers both gradient-free and gradient-based methods for optimization. For parameter estimation, least-squares formulations and general optimization problem formulations are available. Built-in sensitivity studies are also available, where they compute the sensitivity of an objective function with respect to any parameter in the model.

View a list of studies

In many organizations, a small group of numerical simulation experts is servicing a much larger group of people working in product development, production, or as students studying physics phenomena and processes. To make it possible for this small group to service the much larger group, the COMSOL Multiphysics^® software contains functionality for building simulation apps. The Application Builder allows simulation experts to create intuitive and very specific user interfaces for their otherwise general computer models — ready-to-use custom apps.

The general model can serve as a starting point for several different apps, each with its own restricted input and output options relevant for a specific task. Apps are run on a thin client or through a web browser and can include user documentation, checks for “inputs within bounds”, and predefined reports at the click of a button. You can deploy your finished apps to your design teams, manufacturing departments, process operators, test laboratories, customers, and clients worldwide through network or web access via the COMSOL Server™ app-management and distribution tool.