Jennifer Segui | January 9, 2014

Spectroscopic imaging has been used for decades to map the chemical composition of material surfaces with atomic-scale resolution. In order to achieve adequate chemical specificity and spatial resolution during imaging, both the material sample and the imaging system are placed under high or ultra-high vacuum (UHV). In practice, materials are often used outside of vacuum environments and therefore it is also necessary to evaluate their surface properties at higher or ambient pressure. Differential pumping is the key to designing vacuum […]

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Walter Frei | January 8, 2014

When you are working with foreign CAD data, such as files in STEP or IGES file formats, you may think that you need to re-import a new CAD file and start your modeling over from scratch if you want to study a change in size or shape. But, in fact, you can modify the geometry that you’ve imported with some clever usage of the Deformed Geometry interface in COMSOL Multiphysics. Here, we will look at how this can be done.

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Lexi Carver | January 7, 2014

An RF MEMS switch is an electromechanical component found in RF systems. It usually consists of a micromechanical bridge or cantilever, a substrate, and an electrode or dielectric layer. These devices can switch at RF frequencies and tend to have high isolation, i.e. power loss when the switch turns off; low insertion loss (loss of signal power when the switch is on), and extremely low (almost zero!) power consumption. Let’s take a look at how you can use COMSOL Multiphysics […]

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Nicolas Huc | January 6, 2014

In this blog post we will explain the concept of conjugate heat transfer and show you some of its applications. Conjugate heat transfer corresponds with the combination of heat transfer in solids and heat transfer in fluids. In solids, conduction often dominates whereas in fluids, convection usually dominates. Conjugate heat transfer is observed in many situations. For example, heat sinks are optimized to combine heat transfer by conduction in the heat sink with the convection in the surrounding fluid.

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Fanny Littmarck | January 3, 2014

Before conducting certain blood sample analyses, researchers need to separate the red blood cell particles from the blood plasma. Using lab-on-a-chip (LOC) technology, red blood cell separation can be achieved via magnetophoresis, i.e. motion induced by magnetic fields. Since the magnetic permeability of the particles is different from the blood plasma, their trajectory can be controlled within the flow channel of the LOC device and thereby separated out from the fluid.

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Mads Herring Jensen | January 2, 2014

I recently had the pleasure of preparing a small contribution to the 166th Meeting of the Acoustical Society of America (Fall 2013) together with Wade Conklin and Jordan Schultz from Knowles Electronics. Wade presented our paper entitled “Characterization of a microelectromechanical microphone using the finite element method”. The work consisted of implementing a virtual prototype of a Knowles MEMS microphone (the SPU0409LE5H microphone, see picture below) using COMSOL Multiphysics.

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Mateusz Stec | January 1, 2014

Computer aided engineering (CAE) helps us understand how mechanical systems work before they are physically realized. In order to properly reflect the reality, we continuously increase the modeling complexity when we simulate, validate, or optimize our applications. A simple technique to improve a model is to increase the number of finite elements that in turn create more evaluation points. The hardware and simulation time, however, may limit the size of the model, and other solutions are necessary — such as […]

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Chris Pinciuc | December 31, 2013

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.

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Alexandra Foley | December 30, 2013

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 […]

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Walter Frei | December 27, 2013

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. […]

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Walter Frei | December 26, 2013

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.

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