New Products in Version 4.2

The following new products are introduced with COMSOL Multiphysics version 4.2:

  • Electrodeposition Module: A new module intended for investigating the influence of different parameters, in an electrodeposition cell, on the thickness and composition of electrodeposited metal layers. See “Electrodeposition Module” on page 21 for more information.
  • Microfluidics Module: A new module that includes laminar flow capabilities for single-phase and multiphase flow, including Knudsen slip conditions for microchannels. The module also features a tailored molecular flow interface. See “Microfluidics Module” on page 30 for more information.
  • Geomechanics Module: An add-on to the Structural Mechanics for modeling soil mechanics and other applications in geomechanics. The Geomechanics Module includes a number of well-known material models for soil mechanics and rock mechanics such as the Cam-clay, Drucker-Prager, and Hoek-Brown models. See “Geomechanics Module” on page 23 for more information.
  • LiveLink for AutoCAD®—connects COMSOL Multiphysics with the AutoCAD software.
  • LiveLink for SpaceClaim®—connects COMSOL Multiphysics with the SpaceClaim software.

In addition, the former Earth Science Module is replaced by the Subsurface Flow Module (see “Subsurface Flow Module” on page 37).

New Functionality in Version 4.2

General COMSOL Desktop Functionality

  • New selection tools for creating the following selections:
  • Boolean combinations (union, intersection, difference) of previously defined selections
  • geometric entities that are partially or completely enclosed by a box or a sphere
  • complement of other selections
  • geometric entities (boundaries, for example) that are adjacent to some geometric entity (a domain, for example).
  • resulting entities from operations in the geometry sequence
  • duplicates (copies) of existing selections
  • “Drag-and-drop” nodes in the Model Tree to copy or duplicate nodes.
  • Copy and duplicate nodes in the physics interface branches of the Model Tree.
  • Assignment of units for arguments to a function and the function itself, removing the need to “de-dimensionalize” function inputs and treat function outputs as dimensionless.
  • Improved separate Log window and Progress window. The Progress window is cleared automatically when the solver or other process that the progress indication concerns has finished. In the Log window it is possible to clear the contents and to stop and resume the scrolling of the log window contents. There are also clear dividers in the log when starting a new model or opening a model to separate the log contents.
  • Rendering of materials now include appearance, see the figure above: In 2D that includes color and in 3D color, texture, and reflectance. There are predefined appearance groups for common materials (aluminum, copper, gold, iron, water, air, brick, concrete, plastic, and others) are available, and you can also define custom appearances. To enable texture rendering, set the Preferences>Graphics settings so that Quality is selected from the Optimize for list.
  • New 2D renderer with better axis labels, easier selection of overlapping pair boundaries, and a new drawing table with grid and rulers that show the position of the pointer; see the figure below.
  • Automatic creation of identity and contact pairs in assemblies and easier conversion between pair types.

Geometry and Mesh

  • Parametric surfaces make it possible to create 3D surfaces based on coordinate functions using two surface parameters, see the figure below.
  • Virtual geometry that can simplify final analyzed 3D geometries for improved meshing and easier physics modeling. You can add additional features to a finalized geometry to:
  • Ignore vertices and edges
  • Form composite edges and faces
  • Collapse edges
  • Merge vertices
  • Improved mesh generators that support the virtual geometry operations.
  • The import of meshes from NASTRAN files optionally includes materials.

Physics Interfaces

  • New Coefficient Form PDE and General Form PDE interfaces on boundaries, edges (3D), and points (2D and 3D).
  • New Domain ODEs and DAEs, Boundary ODEs and DAEs, Edge ODEs and DAEs (3D), and Point ODEs and DAEs (2D and 3D) for solving distributed ODEs and other space-independent equations on domains and boundaries, along edges, or at points in the geometry.
  • Heat Equation and Convection-Diffusion Equation are now available in the Classical PDEs section of the Mathematics interfaces.
  • New Thin Diffusion Barrier boundary condition for interior boundaries in the Transport of Diluted Species interface.

Studies and Solvers

  • Time-dependent adaptive mesh refinement during solution of time-dependent problems. The example below in the figure below is from the inkjet model in the Microfluidics and CFD Modules Model Libraries. The phase boundary between air and ink is here resolved using time-dependent adaptive meshing.
  • Automatic remeshing for models that involve moving meshes. The figure below shows the squeezed element generated by a moving boundary and the resulting elements after remeshing at the same time step. The model is available in the Electrodeposition Module Model Library.
  • Parallel assembly and solvers provide much improved scalability of solver performance for cluster computing and distributed-memory parallelism.
  • Substantially increased performance for the assembly process.
  • Convergence plots for monitoring convergence of nonlinear, iterative, and time-dependent solvers.


  • Improved plot defaults that provide plots adapted to the physics in the model with descriptive names of the created plot groups.
  • Histogram plots.
  • Nyquist plots. The figure below shows the Nyquist plot from an AC-impedance analysis of a fuel cell at two different electrolyte conductivities. The model is available in the Batteries & Fuel Cells Module’s model library.
  • New Thermal Light color scale, which is the default color scale for predefined temperature plots.
  • RMS (root mean square or quadratic mean) and variance of data series.
  • Direct results output of location for maximum and minimum.
  • Frequency spectra using FFT now include scaling and units.
  • Data export using grid format.
  • Line markers at data points in graph plots.
  • Improved arrow plots: logarithmic arrow scaling, cone arrows in 2D, and optional filtering of data for arrow plots.
  • Improved positioning of color legends (color scales): to the right, to the left, above, below, or on alternating sides of the plot.
  • Possibility to “symmetrize” the color range in plots (around zero, for example) for improved visualization of wave propagation.
  • Direct copying of the contents in the Graphics window to the Windows clipboard for pasting the plot into a word processing document or spreadsheet, for example, using Ctrl+C and Ctrl+V.

Physics Interface Builder (Beta Version)

The Physics Interface Builder is a new tool for building custom applications and physics interfaces directly in the COMSOL Desktop environment. From the File menu, choose New>Physics Interface Builder to start a new Physics Interface Builder. The Physics Interface Builder window then replaces the Model Builder window. In a similar way that you build models using existing physics interfaces, you can build custom physics interfaces using the building blocks in the Physics Interface Builder and test them interactively. These custom physics interfaces can be fully deployed, including support for localization of the user interface. See the Physics Interface Builder User’s Guide for more information and examples of how to use the Physics Interface Builder.

Report Generator

Version 4.2 includes a report generator that you can use to generate HTML reports of models. The report generator is an integrated part of the model, and you can add several reports to a model. There are four predefined templates:

  • Brief Report: provides an overview of the model
  • Intermediate Report: provides the most important information about the model
  • Complete Report: provides full information about the model
  • Custom Report: an initially empty report that you can fully configure

In all reports you can move, add, disable, and delete report nodes to adjust the report contents.

By default, the reports include a table of contents with clickable links to the contents below. The report generator uses a built-in stylesheet, but you can use a custom stylesheet to change the appearance of the report in the web browser.

For more information, see “Creating Reports” in the COMSOL Multiphysics User’s Guide.

The reports in version 4.2 do not include the following parts of a model:

  • Probes
  • Model couplings
  • Coordinate systems
  • Pairs
  • Solver
  • Data sets
  • Export

The reports will include all applicable parts of the model in version 4.2a.

Note: You find the tools for creating data files, images, and animations under the Report branch in version 4.1 under the Export branch in version 4.2.

Backward Compatibility vs. Version 3.5a

Deformed Geometry Interface

The Parameterized Geometry application mode in versions 3.5a, which is limited to 2D, is replaced with the Deformed Geometry interface in version 4.2. This interface is available in 2D and 3D. The Deformed Geometry interface deforms the mesh using an arbitrary Lagrangian-Eulerian (ALE) method and is not the parameterized geometry using geometric parameter sweeps (see above).

In the version 4.2 interface, the Linear Displacement and Similarity Transform boundary conditions are not yet available as preset conditions. Those boundary conditions are planned for version 4.2a.

In version 4.2, you can create the corresponding conditions by manually entering variables.

Backward Compatibility for pre-3.5a models

COMSOL 4.2 can load models saved from version 3.5a. For loading models from earlier COMSOL versions than 3.5a you need to load them in COMSOL 3.5a and then save them. For simplifying this task a utility is available where you can convert all files in a directory from versions 3.0–3.5 to version 3.5a. See the section “COMSOL Convertpre35a Command” for Windows, the section “COMSOL Convertpre35a Command” for Linux, or the section “COMSOL Convertpre35a Command” for the Mac in the COMSOL Installation and Operations Guide for more information.