How to Perform a Nonlinear Distortion Analysis of a Loudspeaker Driver

Kirill Shaposhnikov June 18, 2018

A thorough analysis of a loudspeaker driver is not limited to a frequency-domain study. Some desirable and undesirable (but nonetheless exciting) effects can only be caught by a nonlinear time-domain study. Here, we will discuss how system nonlinearities affect the generated sound and how to use the COMSOL Multiphysics® software to perform a nonlinear distortion analysis of a loudspeaker driver.

Weiterlesen

Thomas Forrister June 5, 2018

The greenhouse effect has made it necessary for scientists to develop combustion processes that minimize the accumulation of carbon dioxide in the atmosphere. Possible fuels in these processes include biomass and other biofuels, which recycle carbon within a short timescale. But there’s a downside: Combustion of these materials produces carbon and ash particles that must be removed from the exhaust. To improve particle filtration, researchers studied electrostatic filter designs using models that were validated by comparing them to experimental data.

Weiterlesen

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.

Weiterlesen

Kategorien

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.

Weiterlesen

Kategorien

Walter Frei April 17, 2018

In applications such as power transfer and consumer electronics, it may be critical to model electromagnetic heating of materials that are nonlinear in temperature; that is, the material’s electrical conductivity and thermal conductivity vary with temperature. When modeling these nonlinearities, even an experienced analyst can sometimes get quite unexpected results due to the combination of the nonlinear material properties, boundary conditions, and geometry. Let’s find out why this is in terms of a very simple example.

Weiterlesen

Bridget Paulus April 9, 2018

Acyclic generator, unipolar generator, disc dynamo, Faraday wheel — No matter what you call it, the homopolar generator is an interesting device. Unlike most generators, homopolar generators produce high current with low voltage and can store and release large amounts of electricity. Due to these abilities, scientists have worked to improve this device since its invention. To continue this work, you can evaluate the performance of homopolar generator designs using the COMSOL Multiphysics® software.

Weiterlesen

Kategorien

Thomas Forrister March 22, 2018

In the 1970s and 80s, music fans would dedicate entire rooms of their homes to stereo systems. Big, boxy loudspeakers were essential fixtures of these stereo setups. Today, a new trend has emerged: Consumers want loudspeakers that are both powerful and portable, with the ability to connect to devices around the house and on the go. To design sophisticated yet lightweight loudspeakers, you can optimize the topology of their components, such as a magnetic circuit for the loudspeaker driver.

Weiterlesen

Cesare Tozzo January 23, 2018

Ferromagnetic materials are ubiquitous in electronic components and electrical machinery. In EM modeling, we may be interested in the broader application or focus on a certain material characteristic (e.g., the mechanical resistance of structural steel) that happens to be magnetic. In both cases, ferromagnetic parts influence the magnetic field in their surroundings, and identifying exactly how this happens could be crucial to the proper functioning of a device or system.

Weiterlesen

Kategorien

Edmund Dickinson January 17, 2018

As two of the greatest mathematicians to have ever lived, Leonhard Euler and Joseph-Louis Lagrange made numerous contributions to continuum mechanics. Combining their individual descriptions of the subject inspired the arbitrary Lagrangian-Eulerian (ALE) method, a technique that can be used for a multitude of simulation applications. Find out how the work of Euler and Lagrange helped create the ALE method and how it aids your simulations in the COMSOL Multiphysics® software.

Weiterlesen

Brianne Costa December 29, 2017

Want a roadmap to modeling cables? We have a six-part tutorial series for you. The Cable Tutorial Series shows how to model an industrial-scale cable in the COMSOL Multiphysics® software and add-on AC/DC Module, and also serves as an introduction to modeling electromagnetic phenomena in general. The numerical model is based on standard cable designs and validated by reported figures. Keep reading for a sneak peek of what you’ll learn when you roll up your sleeves and start the series.

Weiterlesen

Kategorien

Caty Fairclough December 8, 2017

Within mass spectrometers, plasmas are often used to ionize a sample and an inert background gas. Before the ions produced in the plasma are sent into the mass filter, which determines the sample’s chemical composition, they must be focused into a beam with a suitably small radius. One way to focus ions is with an ion funnel. Focusing ions is a critical stage of the overall design, so it’s important to have a fundamental understanding of the funnel’s operating principles.

Weiterlesen


Kategorien


Tags

1 2 3 10