## Thermal Modeling of Phase-Change Materials with Hysteresis

##### 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…

Read More##### 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.

Read More##### 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…

Read More##### 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.

Read More##### 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.

Read More##### Lexi Carver February 3, 2016

Adding annotation plots to your plot groups is an easy way to label the plots of your simulation results with names, comments, and values of quantities evaluated at specified locations. In this blog post, we’ll explore adding annotation plots to a model of a heat sink.

Read More##### 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.

Read More##### Nikola Strah January 25, 2016

Surely you remember the last time you were stuck in bed with the flu. Influenza, commonly known as the flu, can be at the very least an unpleasant experience, but it also claims a lot of casualties every year. Today, public health officials use mathematical modeling techniques to study the flu and other infectious diseases to predict their spread and make informed decisions about public health.

Read More##### Nancy Bannach January 12, 2016

Modeling complex geometries with thin structures can be very costly in terms of computational effort, particularly as such structures require quite a lot of mesh elements in order to resolve them. COMSOL Multiphysics provides dedicated features for modeling thin structures so that such models can be solved efficiently while maintaining accuracy. To set up and postprocess thin structures, COMSOL Multiphysics also provides specialized operators to help you consider all the relevant parameters required for accurate results.

Read More##### Walter Frei January 5, 2016

It has been a remarkably warm winter in Boston, but we finally got our first snowfall. As I was staring out the window earlier, I started thinking about snowflakes and how their formation cannot be easily described mathematically. However, there is one special kind of snowflake that can be simply described, known as the Koch snowflake. Today, we will look at how this shape can be built with the Application Builder in COMSOL Multiphysics.

Read More##### Walter Frei December 29, 2015

While designing a structure, have you ever been unsure of how to achieve the best shape? If so, then you will want to add a useful technique called shape optimization to your COMSOL Multiphysics modeling skill set. Today, we will discuss the concept of shape optimization and demonstrate its use through a classical problem.

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