Easier, faster problem setup
An aspect that makes it easier for the average engineer to successfully create models is the increased number of predefined multiphysics couplings. Users know intuitively what they want to do, for example, evaluate fluid-structure interaction. Until now, though, to implement unusual or extremely complex models they have needed a fairly thorough knowledge of the underlying physics along with familiarity of COMSOL Multiphysics’ dialog boxes and the overall problem structure. Now they simply select ready-made couplings from a menu with the correct physics, boundary settings, and couplings already set up. Users then quickly modify this interface to meet the specific needs of the geometry.
A number of new predefined multiphysics couplings join an already comprehensive selection. These include microwave heating, induction heating, rotating machinery, fluid-thermal interactions for laminar, nonisothermal and turbulent flow, and fluid-structure interaction.
A major addition to the COMSOL Multiphysics graphical user interface is the Model Tree. This separate window gives an overview of all aspects of a model by means of a menu-tree view that users can navigate to inspect and modify context-specific features and settings. All variables, parameters, constants, and expressions are accessible from the Model Tree. A special condensed view shows only where a user has made modifications that deviate from default settings.
Solving made straightforward, more transparent
When a model is set up, the software now takes a first step towards fully automating the solver choice, a choice that is fully aware of the mathematics and numerical schemes required to solve the multiphysics couplings. The version also adds the PARDISO solver—a shared-memory parallel algorithm that works well as a powerful direct solver applicable to, for example, large electromagnetic models.
During the solution process a realtime probe-plot feature tracks the value of any selected variable and graphs this scalar value in real time. Similarly, while the software is calculating the solution, users can monitor a convergence plot that shows the solver’s progress on a realtime graph.
Parts and assemblies
Most CAD engines typically work with parts and assemblies, and COMSOL Multiphysics now supports them throughout the modeling process. Rather than import an assembly as a single unit, COMSOL Multiphysics now recognizes its constituent components, each with multiple parts, for instance to allow for different materials in each one. Parts and their physics can be coupled through a feature that allows for continuity or allows users to define other internal border definitions such as contact resistance.
Users can also start working with a library of components where each contains not only a geometry but also a specific physics definition, boundary settings, and set of material properties. Two or more components are then merged to build a more comprehensive system, process, or assembly, all without each component’s settings being lost. This is ideal for a user investigating many different models that vary only in a certain part or section of the overall makeup.
It is possible to optimize the mesh locally for each part or model subdomain through the interactive meshing environment. This makes it possible to build a mesh in an incremental fashion where each meshing operation acts on a set of subdomains. For example, users can start by creating a boundary mesh and then mesh each subdomain sequentially. Furthermore, using interactive meshing they can apply different meshing techniques to different domains of a geometry object. Outside of the obvious benefits for matching a mesh to a subdomain’s geometry, this feature also provides improved flexibility as sometimes the mesh must suit the physics found within one subdomain that may not exist in other subdomains. The interactive meshing feature does not require a nodal match on the boundaries between the different subdomains, instead connection occurs through the mathematics of the numerical scheme.
Using the new swept meshing tool, which is fully integrated in the interactive meshing environment, users can easily create prism (wedge) meshes and hexahedral (brick) meshes.
The Structural Mechanics and MEMS Modules now offer increased support for contact problems to bring to the industry the first tool for true Multiphysics Contact applications. Identifying contact pairs at the geometry-creation stage, users can now model contact and couple it with their other physics. Heat flux, electric current, and species diffusion generated at, or flowing across contact surfaces, can now be modeled and coupled to the material properties of the contact materials. This means, for example, that COMSOL can model the generation of heat from contact friction and simultaneously couple and solve this with contact and material properties that vary with the generated heat.