# COMSOL Multiphysics

## Discontinuous Galerkin Method

The significant flexibility of COMSOL Multiphysics represents one of the primary reasons AltaSim uses this software as our main simulation tool. In this installment of our Tips & Tricks, we are going to review the discontinuous Galerkin (DG) method that COMSOL has implemented. AltaSim has found that for the cases described in this article, DG […]

## Selection of Exterior Boundaries

At virtually every step of the model creation process, you need to select and apply materials, physics boundary conditions, and other settings to your model geometry. Bookkeeping of these settings can be challenging, especially when you re dealing with large, complex geometries and multiple physics interfaces. In COMSOL Multiphysics, Selections provides a tool to organize your model

## Adaptive Meshing for CFD

Developing solutions using Computational Fluid Dynamics (CFD) often challenges simulation engineers. These simulations may require long computational times and large amounts of computer memory. AltaSim regularly solves complex CFD problems and finds that meshing is a critical component for run-time and computer memory issues. To help you solve your CFD problems with less frustration and

## Default Model Inputs

As COMSOL Multiphysics evolves, methods to include important features in simulations change. Coupling temperatures to different physics is a common need for multiphysics simulations. COMSOL has made changes that effect temperature coupling. Our clients have asked about the warning signs they get when using temperature coupling, and we would like to share with you our

## Temperature-Dependent Coefficients of Thermal Expansion

Making accurate physics predictions using simulations requires a knowledge of the material properties and how to implement them correctly in the software. This is particularly important in analyses involving thermal expansion when the coefficients of thermal expansion (CTEs) of the materials vary significantly with temperature. For example, optical devices that operate in the vacuum of

## Rigid Motion Suppression

Incorrect boundary conditions in finite element analysis (FEA) lead to incorrect solutions, or the simulation does not converge. To develop a converged solution, all FEA models require constraining each dependent variable somewhere in the model. Typically, this is done directly onto the model region geometry, but it can also be accomplished through Robin conditions. This

## How to Export Plot Data in COMSOL Multiphysics

Post processing is the last of the five primary steps of simulation development. This step represents the payoff from all the hard work of the previous steps, and it drives the deeper understanding of the design that engineers obtain though simulation. A simulation engineer can significantly improve their understanding, and better communicate that understanding, when

## Improved Solver Settings Feedback

At AltaSim, we take time to evaluate each new release of COMSOL Multiphysics. The changes that COMSOL implements can have a significant impact on how to use the software. Having a deep understanding of these changes helps us serve our clients better. We also pass on our insights via Tips & Tricks so you can benefit

## Solver Improvement in COMSOL Multiphysics Version 5.6

At AltaSim, we await COMSOL’s improvements to their software with great anticipation.  We take time to evaluate these changes to determine what we can use to better serve our clients.  Based on our review, we also pass on our insights via Tips & Tricks. Version 5.6 of COMSOL Multiphysics has introduced serval solver improvements that

## Data Storage Options for Dynamic Simulations

Many simulations are quasi-static, or steady state, because the results are independent of time.  Time dependent simulations introduce additional challenges over time independent cases.  The data generated during a time dependent simulation could be many gigabytes.  Thus, the simulation engineer needs to balance the volume of output data with their needs for data at critical