Latest Posts
Parameterizing the Dimensions of Imported CAD Files
Learn how to modify an imported geometry with some clever usage of the Deformed Geometry interface in COMSOL Multiphysics®.
Simulating an RF MEMS Switch
An RF MEMS switch is typically made up of a micromechanical bridge or cantilever, a substrate, and an electrode or dielectric layer. You can design such a device using RF simulation.
Conjugate Heat Transfer
Get an introduction to the concept of conjugate heat transfer and see some of its applications and modeling considerations.
Red Blood Cell Separation from a Flow Channel
Lab-on-a-chip technology can be used to separate red blood cell via magnetophoresis — for example, motion induced by magnetic fields. Simulation can be used to optimize such devices.
MEMS Microphone Model Presented at ASA 166 in San Francisco
What is a MEMS microphone? Learn about this versatile device, as well as how to model it using COMSOL Multiphysics® with the add-on MEMS Module and Acoustics Module.
Submodeling: How to Analyze Local Effects in Large Models
Modeling a particularly large structure with a lot of boundary conditions? Learn how to use submodeling, a technique for analyzing local effects in large models in COMSOL Multiphysics®.
Visualization for 2D Axisymmetric Electromagnetics Models
Today we’ll look at how to make 3D plots of vector fields that are computed using the 2D axisymmetric formulation found in the Electromagnetic Waves, Frequency Domain interface within the RF and Wave Optics modules.
The Linac-MR Project: Tumor Tracking and Treatment
Not too long ago, my colleague Jennifer wrote a blog post about the Cross Cancer Institute, and the research being conducted there into the design of a new device for treating cancerous tumors. The device, known as the Linac-MR, is revolutionary due to its ability to both image and treat cancer cells simultaneously — a capability that had previously been regarded as near impossible due to the conflicting physics interactions involved. Such a device would allow for extremely precise radiation […]
Using Adaptive Meshing for Local Solution Improvement
One of the perennial questions in finite element modeling is how to choose a mesh. We want a fine enough mesh to give accurate answers, but not too fine, as that would lead to an impractical solution time. As we’ve discussed previously, adaptive mesh refinement lets the software improve the mesh, and by default it will minimize the overall error in the model. However, we often are only interested in accurate results over some subset of the entire model space. […]
Learning to Solve Multiphysics Problems Effectively
One of the questions we get asked often is how to learn to solve multiphysics problems effectively. Over the last several weeks, I’ve been writing a series of blog posts addressing the core functionality of the COMSOL Multiphysics software. These posts are designed to give you an understanding of the key concepts behind developing accurate multiphysics models efficiently. Today, I’ll review the series as a whole.
Optimizing Recloser Performance with Simulation
During snow storms or windy days, a branch might break and short-circuit a power line’s electric current as it falls. The first task of a recloser is to interrupt this short-circuit, i.e. to open or disconnect the affected overhead line from the feeding network source. The second task is to try to re-establish power after a short time by to re-closing the line, taking advantage of the fact that most of the reasons for a short-circuit of an overhead line […]
Improving Convergence of Multiphysics Problems
In our previous blog entry, we introduced the Fully Coupled and the Segregated algorithms used for solving steady-state multiphysics problems in COMSOL. Here, we will examine techniques for accelerating the convergence of these two methods.
Modeling Bone Strength Using Isotropic and Anisotropic Materials
The question of exactly how strong living bones are poses many important considerations for the medical industry. There is not currently a single-purpose device in the field to test bone strength. However, it is possible for researchers to get measurements of bone strength by modeling the entire makeup of the bone and using multiphysics simulation to perform stress and strain analyses. Simulating bone strength starts with a simple map of the external topology of the bone and then delves into […]
Optimizing Dialyzer Design Using Multiphysics Simulation
A while back, I had the opportunity to speak with Steven Conrad, a critical care physician at the Louisiana State University (LSU) Health Science Center in New Orleans. Not only is Dr. Conrad a physician as well as a professor at LSU, he’s also a biomedical engineer who uses finite element analysis (FEA) to conduct research on the design of dialyzers. Dr. Conrad uses COMSOL Multiphysics to gain a deeper understanding of the physics behind these devices, and to create […]
Simulating Viscous Fingering Using Equation-Based Modeling
A prospective user of COMSOL approached me about modeling viscous fingering, which is an effect seen in porous media flow. He hadn’t found a satisfying solution elsewhere, so he turned to COMSOL. I’d like to share with you some of my insight on how to go from idea to model to simulation by taking a “do-it-yourself approach” and utilizing the equation-based modeling capabilities of COMSOL Multiphysics.
Predicting Microwave Drying of Potatoes
You may not think of reheating food in the microwave as a drying process, but as we saw at the COMSOL Conference 2013 Boston, microwave technology — the same technology used in domestic microwave ovens — can be used for drying fruits and vegetables. One poster presented at the conference featured microwave drying of potatoes and how the heat and mass transfer that occurs can be modeled to predict the drying process.
Solving Multiphysics Problems
Here we introduce the two classes of algorithms used to solve multiphysics finite element problems in COMSOL Multiphysics. So far, we’ve learned how to mesh and solve linear and nonlinear single-physics finite element problems, but have not yet considered what happens when there are multiple different interdependent physics being solved within the same domain.
2D Materials, It’s Not Just About Graphene
You’ve heard the story: a couple of scientists discovered graphene when they repeatedly pulled a strip of adhesive tape off a layer of graphite. Graphene has been all the rage due to its incredible strength, low weight, and electronic properties, but it’s not the only material of its kind. There are plenty of other 2D materials to consider for electrical applications — some of which may work together with graphene, and others that can be used in its place.
Thermal Modeling of Surfaces with Wavelength-Dependent Emissivity
Whenever we are solving a thermal problem where radiation is significant, we need to know the emissivities of all of our surfaces. Emissivity is a measure of the ability of a surface to emit energy by radiation, and it can depend strongly upon the wavelength of the radiation. This is very relevant for thermal problems where the temperature variation is large or when there is exposure to a high-temperature source of radiation such as the sun. In this post on […]
Microwave Plasmas
Microwave plasmas, or wave-heated discharges, find applications in many industrial areas such as semiconductor processing, surface treatment, and the abatement of hazardous gases. This blog post describes the theoretical basis of the Microwave Plasma interface available in the Plasma Module.
Meshing Considerations for Nonlinear Static Finite Element Problems
As part of our solver blog series we have discussed solving nonlinear static finite element problems, load ramping for improving convergence of nonlinear problems, and nonlinearity ramping for improving convergence of nonlinear problems. We have also introduced meshing considerations for linear static problems, as well as how to identify singularities and what to do about them when meshing. Building on these topics, we will now address how to prepare your mesh for efficiently solving nonlinear finite element problems.
Photos from the COMSOL 4.4 Launch Event in Silicon Valley
In anticipation of the COMSOL 4.4 release, the COMSOL office in Palo Alto decided to try something new. Feeling inspired by the very successful COMSOL Conference in Boston, we held an all-day launch event in Silicon Valley. Here’s a round-up of the event and some of the photos we took.
New Mixer Module Showcases CFD Capabilities of COMSOL
The Mixer Module provides ready-made interfaces for describing the difficult problem of laminar and turbulent flows in rotating machinery with free liquid surfaces. COMSOL has been developing different techniques for modeling CFD, moving geometries, and free surfaces during the past few years for a number of different applications. This has now culminated in the new Mixer Module that was released with version 4.4, and it clearly showcases the improved CFD capabilities of COMSOL.
COMSOL 4.4 Brings Particle-Field and Fluid-Particle Interactions
The trajectories of particles through fields can often be modeled using a one-way coupling between physics interfaces. In other words, we can first compute the fields, such as an electric field, magnetic field, or fluid velocity field, and then use these fields to exert forces on the particles using the Particle Tracing Module. If the number density of the particles is very large, however, the particles begin to noticeably perturb the fields around them, and a two-way coupling is needed […]