## How to Optimize the Spacing of Electromagnetic Coils

##### Walter Frei April 20, 2017

Did you know that you can maximize the magnetic field strength of your electromagnetic coil designs by optimizing the spacing between the coils?

### 3 Ways to Optimize the Current in Electromagnetic Coils

##### Walter Frei April 10, 2017

We give you 3 ways to optimize the current in electromagnetic coil designs using the AC/DC Module and Optimization Module, add-on products to COMSOL Multiphysics®.

### How to Postprocess Fields over Arbitrary Geometries

##### Walter Frei April 4, 2017

Check out this useful modeling trick: You can query the results of your model within an arbitrary geometric subregion by implementing an integration during postprocessing.

### How to Compute Distances Between Objects in COMSOL Multiphysics®

##### Walter Frei March 2, 2017

Compute the distance between two deforming objects in the COMSOL Multiphysics® software. Here’s how…

### How to Model the Electromagnetic Heating of Underground Cables

##### Walter Frei February 14, 2017

Underground power cables are beneficial in many ways, but they are also subject to overheating. To design better cables, we can model their electromagnetic heating in COMSOL Multiphysics.

### Part 2: Modeling the Harmonic Excitations of Nonlinear Systems

##### Walter Frei August 11, 2016

Extending our discussion on modeling the harmonic excitations of linear systems, we will now shift focus to nonlinear systems. We will look at problems where the loading on the system has some sinusoidal components as well as cases where the material properties or loads and constraints depend directly on the solution. As you will see, COMSOL Multiphysics can address these apparently nonlinear cases with some very efficient solution algorithms. Let’s find out how.

### Part 1: Modeling the Harmonic Excitations of Linear Systems

##### Walter Frei August 10, 2016

In many engineering situations, we can assume that excitations on the system of interest and the responses are sinusoidal over time. When this assumption holds, we can use a so-called frequency-domain analysis, which leads to some very efficient solution techniques. Let’s go over a few basic concepts and the conditions under which we can make this assumption, while exploring various solution approaches to take.

### How to Implement a Delay in Your Thermostat Simulation

##### Walter Frei June 30, 2016

Thermostats are used in most homes for controlling furnaces and air conditioners to maintain a comfortable interior temperature. A simple thermostat controlling a heater will have on and off setpoints. Such a control scheme is easy to implement within COMSOL Multiphysics using the Events interface, as presented in a previous blog post. Today, we will expand this technique to include a delay, a time lag between turning the heater on or off, in a thermostat simulation.

### Thermal Modeling of the Air Flow Inside and Around Your House

##### Walter Frei June 22, 2016

Have you ever wanted to quickly predict the temperature of an enclosed structure that is exposed to ambient environmental conditions, such as your house? The temperature inside depends on the surrounding air temperature, wind speed, and solar loads, all of which have significant variability. For simplicity, we often also want to approximate the inside air as well-mixed. Today, we will discuss the tools in the COMSOL Multiphysics® software that help you quickly build such thermal models.

### Exporting Meshes and Solutions Using the Application Builder

##### 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!

### Modeling Thermal Ablation for Material Removal

##### Walter Frei March 30, 2016

Whenever solid materials are heated enough, they will melt and then vaporize to a gas. Certain materials will even go directly from the solid to the gas phase, a process referred to as sublimation or ablation. If the material is heated strongly enough, there will be significant material removal. Today, we will look at how you can model this process in COMSOL Multiphysics.