## How to Implement the Fourier Transformation in COMSOL Multiphysics

##### Yosuke Mizuyama | May 30, 2016

In a previous blog post, we discussed simulating focused laser beams for holographic data storage. In a more specific example, an electromagnetic wave focused by a Fourier lens is given by Fourier transforming the electromagnetic field amplitude at the lens entrance. Let’s see how to perform this integral type of pre- and postprocessing in COMSOL Multiphysics with a Fraunhofer diffraction example.

##### Caty Fairclough | May 9, 2016

Have you ever wondered how tigers develop their stripes? Alan Turing’s theory of morphogenesis offers one possible explanation for this occurrence, suggesting that patterns, such as stripes, develop naturally from initially homogeneous states. Today, we’ll take a closer look at Turing’s theory and explore some modern research on this topic, including the modeling of branching morphogenesis in COMSOL Multiphysics.

##### Walter Frei | April 6, 2016

Have you ever wanted to write out mesh and analysis data from COMSOL Multiphysics into a text file? You may want to do this when passing information to another software program or even just into a spreadsheet. You often want to customize the exact format in which such data is written, depending upon the needs of the other tools with which you are working. This is very easy to do with the Application Builder. Let’s find out how!

##### Walter Frei | March 16, 2016

Thermal curing is the process of temperature-induced chemical change in a material, such as the polymerization of a thermoset resin. This process is relevant, for example, when a precursor resin is heated and hardens during the manufacturing of composites. You can often assume that the material does not flow during curing, which simplifies the analysis. Thermal curing is very easy to model within the core functionality of COMSOL Multiphysics, as we will show in this blog post.

##### Walter Frei | March 2, 2016

Have you ever wanted to rapidly set up a COMSOL Multiphysics model with hundreds of different parts? If so, you might not want to use a graphical user interface where you manually enter dimensions and properties for each part. Generating a text file that contains all of this information offers a much faster route. Today, we will look at how you can use the Application Builder to quickly convert a text input file into a COMSOL model.

##### Magnus Ringh | April 27, 2016

You can use the residual operator, new with COMSOL Multiphysics version 5.2, to evaluate and plot your model’s algebraic residual in order to troubleshoot convergence issues. This blog post demonstrates the use of the residual operator for visualizing and understanding the convergence properties of a turbulent flow simulation.

##### Walter Frei | March 24, 2016

In today’s blog post, we will introduce a procedure for thermally modeling a material with hysteresis, which means that the melting temperature is different from the solidification temperature. Such behavior can be modeled by introducing a temperature-dependent specific heat function that is different if the material has been heated or cooled past a certain point. We can implement this behavior in COMSOL Multiphysics via the Previous Solution operator and a little bit of equation-based modeling. Let’s find out how…

##### Walter Frei | March 8, 2016

Have you ever had a set of nonuniformly distributed points in a Cartesian plane that sample a surface height, such as points on the contours of a map or data points representing some material property data? If so, you probably also wanted to reconstruct, or interpolate, a continuous and smooth surface between these points. You can construct such a surface using the core capabilities of COMSOL Multiphysics by using Radial Basis Functions. Let’s find out how…

##### Walter Frei | February 22, 2016

Whenever you are building a finite element model in COMSOL Multiphysics, you should be aware of the element order that is being used. This is particularly important for multiphysics models as there are some distinct benefits to using different element orders for different physics. Today, we will review the key concepts behind element order and discuss how it applies to some common multiphysics models.

##### Bjorn Sjodin | February 2, 2016

Have you ever run a large parametric sweep overnight, only to discover the next morning that the parametric solver is still not finished? You may wish you could inspect the solutions for the parameters that are already computed while waiting for the last few parameters to converge. The remedy to this problem is to use a batch sweep, which automatically saves the parametric solutions that were already computed on a file that you can open for visualization and postprocessing purposes.