Latest Posts

COMSOL Multiphysics Version 4.4 Released Today
You’ve seen glimpses of our new software release at the COMSOL Conference and perhaps engaged in commentary around it in social media. Today marks the official release of COMSOL Multiphysics version 4.4, and you can now learn about the software updates in detail and download it if you are on subscription.

Your Room, from Interior Design to Acoustics
I recently stumbled upon a neat tool from Autodesk® called “Autodesk® Homestyler”. It’s surprising to see they have rolled out a tool that is more entertaining than utilitarian, but if a CAD company were to develop something fun for the general population, I suppose an interior design app makes sense. We took it for a test-drive. Here’s how it went.

The Next Generation of Moore’s Law
At the COMSOL Conference in Boston, Lam Research Corporation held a keynote talk about Moore’s law and its role in computational modeling. The keynote touched on how Moore’s law has not only impacted the advancement of simulation tools, but also how the development of these tools have themselves allowed Moore’s law to hold true. The concept was something that interested me, and I know it’s been on the minds of many electrical engineers as well. Case in point, when browsing […]

Load Ramping of Nonlinear Problems
As we saw previously in the blog entry on Solving Nonlinear Static Finite Element Problems, not all nonlinear problems will be solvable via the damped Newton-Raphson method. In particular, choosing an improper initial condition or setting up a problem without a solution will simply cause the nonlinear solver to continue iterating without converging. Here we introduce a more robust approach to solving nonlinear problems.

Why All These Stresses and Strains?
In structural mechanics you will come across a plethora of stress and strain definitions. It may be a Second Piola-Kirchhoff Stress or a Logarithmic Strain. In this blog post we will investigate these quantities, discuss why there is a need for so many variations of stresses and strains, and illuminate the consequences for you as a finite element analyst. The defining tensor expressions and transformations can be found in many textbooks, as well as through some web links at the […]

Coupling Transport and Solid Mechanics Models for Better Puffed Rice
In my work at COMSOL, it’s always interesting to see how broad the field of heat transfer can be. Far from being limited to steel ingots and CPU fans, researchers often use COMSOL Multiphysics to study heat transfer in food manufacturing. One good example of this is the study of thermal and mechanical effects in the production of puffed rice, which was presented at the COMSOL Conference 2013 in Boston.

Solving Nonlinear Static Finite Element Problems
Here, we begin an overview of the algorithms used for solving nonlinear static finite element problems. This information is presented in the context of a very simple 1D finite element problem, and builds upon our previous entry on Solving Linear Static Finite Element Models.

Mersen Simulates Joule Heating in Busbars and Fuses
Joule heating is a fairly standard type of simulation for COMSOL users nowadays. It involves solving for electrical voltage and temperature fields simultaneously with highly temperature-dependent material properties. Controlling Joule heating is very important when designing and manufacturing electrical systems components. The electric protection group at manufacturing company Mersen France used to base their busbar and fuse designs on trial-and-error, but these days they turn to COMSOL Multiphysics.

Street Sign Buckles in the Wind, COMSOL User Takes Home Prize
A broken street sign turned into an online contest at the Dutch university TU Delft earlier this month. The TU Delft Webcare Team challenged their social media fans to determine what wind speed led the sign to buckle over — and the winner happens to be a COMSOL user. Here’s how Rob Eling solved the street sign challenge using COMSOL Multiphysics.

Thermometer Calibration: When Experimentation Falls Short
The International Temperature Scale of 1990 (ITS-90) is the industry calibration standard for measuring temperatures throughout the world. The National Physical Laboratory (NPL) works to establish and maintain the ITS-90 through experiments, most notably, thermometer calibration. To better understand and overcome the shortcomings of the experimental process, Jonathan Pearce, at the UK’s National Physics Laboratory, turned to simulation. His results yielded fascinating results about the microscopic behavior of the liquid-solid interface during the freezing process.

Exploring the Leidenfrost Effect
The Leidenfrost effect, also known as film boiling, occurs when a liquid comes into contact with a solid that is at a temperature well above the liquid’s boiling point. Upon contact, a layer of vapor forms between the liquid-solid interface, creating a barrier between the two. There are many examples of this phenomenon, ranging from something you may have seen in your kitchen (water “dancing” around in a pan) to things you shouldn’t try at home (dipping your hand into […]

Solutions to Linear Systems of Equations: Direct and Iterative Solvers
In this blog post we introduce the two classes of algorithms that are used in COMSOL to solve systems of linear equations that arise when solving any finite element problem. This information is relevant both for understanding the inner workings of the solver and for understanding how memory requirements grow with problem size.

Research on Microwave Heating and Chemical Applications
There were many interesting posters at this year’s COMSOL Conference in Boston. A couple that caught my eye involved microwave heating and chemical applications. One of them showcases the use of microwave irradiation to speed up chemical reactions. Another — one of the recipients of the Best Poster award — used simulations to optimize their microreactor design with respect to microwave propagation.

Learn about Modeling Vacuum Systems in COMSOL
Until recently, simulation had not been widely used by vacuum system designers because of an absence of commercial simulation tools. Last October, my colleague James Ransley held a webinar about how to model vacuum systems using COMSOL Multiphysics. The webinar was a great success, and it inspired us to produce a dedicated product for modeling vacuum applications: the Molecular Flow Module (new with version 4.3b). This year, on November 21st, James will be giving a webinar explaining the new features […]

COMSOL Conference 2013 Rotterdam Keynotes on Multiphysics Applications
The COMSOL Conference 2013 Rotterdam was well-attended and highly informative. The keynotes were the high point of the event, and they were excellent examples of multiphysics applications. The sophistication of the modeling work presented by Alwin Verschueren of Philips Research Laboratories in Eindhoven, the Netherlands, and Holger Ernst and Christian Schröder of mieletec FH Bielefeld, Germany, was truly spectacular and kept all the attendees enthralled.

Photos from the COMSOL Conference 2013 Rotterdam
The COMSOL Conference 2013 Rotterdam attracted 418 multiphysics users from across Europe. It was the first time that our conference took place in the Netherlands and as a result, we saw a lot of new faces this year among the participants. I would like to thank everyone who attended the event for making it a wonderful experience and show you some impressions of the conference here on the blog.

Meshing Your Geometry: When to Use the Various Element Types
In a previous blog entry, we introduced meshing considerations for linear static problems. One of the key concepts there was the idea of mesh convergence — as you refine the mesh, the solution will become more accurate. In this post, we will delve deeper into how to choose an appropriate mesh to start your mesh convergence studies for linear static finite element problems.

Philosophy of the Ribbon
Over the past few years, Microsoft® has introduced updates to the user interface (UI) for its Office programs. Microsoft® Office 2013 is all about being touch-screen friendly, and Microsoft® Office 2007 brought the Ribbon interface. The Microsoft® Ribbon was designed to be easier to use than the nested drop-down menus of yore. These days, it’s what we’re used to seeing when working with their tools — and we’ve come to appreciate the ease-of-use, guidance, and clear workflow overview it provides. […]

COMSOL Conference 2013 Rotterdam Award Winners
The COMSOL Conference 2013 Rotterdam came to an end last Friday. After dinner on the second day, six contributions were awarded for their outstanding work: three in the Best Paper category and three in the Best Poster category. The moderator of the awards ceremony — Belgian engineer, stand-up comedian, and COMSOL user — Filip Van den Abeele compared COMSOL Multiphysics to a Swiss Army Knife. After looking at the diversity of subjects that is displayed in the award winning papers […]

Photos from the COMSOL Conference 2013 Bangalore
This year, over 260 multiphysics enthusiasts joined us for the COMSOL Conference 2013 Bangalore. While we did see some familiar faces, it was exciting to see plenty of new users at the event. We were able to capture some of the good moments on camera, and would like to share a selection of the photos with you here on the blog.

How to Identify and Resolve Singularities in the Model when Meshing
In our previous post on Meshing Considerations for Linear Static Problems, we found that, in the limit of mesh refinement, the solution to the finite element model would converge toward the true solution. We also saw that adaptive mesh refinement could be used to generate a mesh that would have smaller elements in regions where the error was higher, rather than simply using smaller elements everywhere in the model. In this post, we will examine a couple of common pitfalls […]

Modeling Electroosmotic Flow and the Electrical Double Layer
Microfluidic devices are so small that the micropumps and micromixers that control and mix the fluid inside the device cannot involve any moving components. Instead, they must take advantage of electroosmotic flow. Here, I will describe the concept of electroosmosis and the electrical double layer (EDL), and how to model these in COMSOL, walking you through two example models.

COMSOL Conference 2013 Bangalore Award Winners
After having excellent poster and oral presentation sessions at the COMSOL Conference 2013 Bangalore, winners for the top papers and posters were announced during the award ceremony. Selecting the best ones was indeed the toughest decision that the Program Committee had to make. It was observed that the presenters had conducted rigorous analyses using COMSOL Multiphysics, and many of them also had experimental validation for their work. Now I would like to congratulate the winners once more, and allow you […]

ABB Uses Electrostatic Simulation to Design Tap Changers
Households and industries alike depend on reliable electrical power. To serve the diverse power needs of end users and consumers, the electrical grid is undergoing a major overhaul to upgrade a technology that is over 100 years old. The new infrastructure — the smart grid — is being developed for reliable, economic, and environmentally friendly electrical systems. A great example of equipment for the smart grid comes from ABB. Along with many other products, ABB has introduced the world’s fastest […]