Terminal Velocity, Drag Coefficients, and FIFA World Cup™ Predictions

Ed Fontes June 1, 2018

Every four years, people interested in association football/soccer (a few billion people) talk about the FIFA World Cup™. We at COMSOL are no exception. During coffee breaks and lunches, we are discussing the different teams, players, preparations, and the tiny details that might impact the teams. The ball is an important protagonist of the games. The subject of the ball combines our passion for soccer and physics into one discussion!

Read More

Categories

Ed Fontes May 31, 2018

In a previous blog post, we discussed using field-based methods (level set and phase field) for modeling free surfaces. Another option, moving mesh, can handle free liquid surfaces that do not undergo topology changes. In this blog post, we will demonstrate how to use the moving mesh method for modeling free surfaces and compare the results with field-based methods.

Read More

Categories

Aditi Karandikar May 30, 2018

The Van Allen radiation belts consist of highly energetic charged particles that have become trapped in Earth’s magnetic field. These particles follow the shape of the field and give the belts a doughnut-like appearance. To study the behavior of the particles in the Van Allen belts, scientists can use the Particle Tracing Module, an add-on product to the COMSOL Multiphysics® software.

Read More

Brianne Costa May 29, 2018

The Doppler effect, or Doppler shift, occurs when the movement of an observer relative to a source (or vice versa) causes a change in wavelength or frequency. Discovered by Austrian physicist Christian Doppler in 1803, this phenomenon is experienced in many different ways, such as when an ambulance passes you by and you hear an audible change in pitch. Using the COMSOL Multiphysics® software, you can model the Doppler effect for acoustics applications.

Read More

Categories

Walter Frei May 25, 2018

One of the more common uses of the AC/DC Module, an add-on to the COMSOL Multiphysics® software, is for modeling conductors and other lossy materials in time-varying magnetic fields when there are significant induced currents. The appropriate modeling approach depends upon how quickly the magnetic fields vary over time. Here, we review the basics and describe various modeling techniques to use.

Read More

Categories

Brianne Costa May 24, 2018

Some inventions haven’t changed much since they first came about…even if centuries have passed. For instance, the pop-up toaster was invented in 1921, and although enhancements have been made, it still toasts bread. Paperclips hit the market about 150 years ago and they still hold sheets of paper together. The same is true of the lead-acid battery, a device that was invented in 1859 and operated under the same basic principles as the one currently in your car.

Read More

Thomas Forrister May 23, 2018

Multiphase flow involves the simultaneous flow of fluids of different phases, such as gases and liquid, or solid particles suspended in a fluid. As such, modeling multiphase flow can require multiple approaches. One approach is to use a bubbly flow model to analyze the effects of bubble-induced turbulence. Here, we discuss a benchmark model of liquid and gas flow in a water-filled airlift loop reactor and validate the simulation results with experiments.

Read More

Categories

Thomas Forrister May 21, 2018

Gustave-Gaspard Coriolis was a French physicist with a passion for mechanics. He spent much of his time contemplating the nature of movement in machinery and introduced the concept of kinetic energy in relation to work. When he extended these ideas to rotating machinery, his sphere of influence grew: The Coriolis force and subsequent Coriolis effect are observed in rotating systems with applications in engineering, meteorology, stellar dynamics, and more.

Read More

Categories

Caty Fairclough May 17, 2018

Mount Erebus, one of Earth’s most remote volcanoes, sits covered in snow and ice. These chilly surroundings can be misleading, as Mount Erebus has another claim to fame: It’s the most active volcano in Antarctica. One option for mapping its magma flow is with a technique called magnetotellurics (MT), which measures the electrical resistivity of Earth’s crust. To study and improve MT, engineers can analyze its performance with electromagnetics simulation.

Read More

Categories

Bridget Paulus May 16, 2018

Thanks to their ability to “tune out” specific frequencies, electromagnetic band gaps (EBGs) are found in many different applications. EBGs can suppress unwanted electromagnetic interference (EMI) and increase electromagnetic compatibility (EMC). These structures are commonly used between nearby antennas, which can help minimize undesirable coupling and thereby enhance their performance. However, using an EBG isn’t always a guarantee for better antenna isolation. To analyze the effectiveness of an EBG, engineers can use the COMSOL Multiphysics® software and add-on RF Module.

Read More

Categories

Ed Fontes May 15, 2018

There are four methods for modeling free liquid surfaces in the COMSOL Multiphysics® software: level set, phase field, moving mesh, and stationary free surface. In the first part of this blog series, we discuss the level set and phase field methods, which are field-based methods that describe almost any type of free liquid surface. In part two, we will compare the results from this post with those obtained using the Moving Mesh interface for solving free surface problems.

Read More

Categories


Categories


Tags

1 2 3 4 121