Accurately Analyze Turbomolecular Pumps with COMSOL Multiphysics®

Caty Fairclough August 9, 2017

Studying vacuum system designs can be difficult, since some analysis methods only work when the relative speed of the gas molecules is very large compared to the velocity of the enclosing walls. This is not the case for turbomolecular pumps, which we can model and analyze using a Monte Carlo approach and the Rotating Frame feature in the COMSOL Multiphysics® software. Let’s check out one example below.

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Bridget Cunningham May 24, 2017

Inertial focusing is a useful technique for various applications, particularly within the medical field. Ensuring its effectiveness requires accurately describing the migration of particles as they flow through a channel. Version 5.3 of the COMSOL Multiphysics® software gives you the tools to generate reliable results that agree with experimental data on inertial focusing. Our new benchmark model highlights these capabilities.

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Christopher Boucher September 22, 2016

In the previous installment of this series, we explained two concepts needed to model the release and propagation of real-world charged particle beams. We first introduced probability distribution functions in a purely mathematical sense and then discussed a specific type of distribution — the transverse phase space distribution of a charged particle beam in 2D. Now, let’s combine what we’ve learned and find out how to sample the initial positions and velocities of 3D beam particles from this distribution.

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Christopher Boucher September 19, 2016

Previously in our Phase Space Distributions in Beam Physics series, we introduced probability distribution functions (PDFs) and various ways to sample from them in the COMSOL Multiphysics® software. Such knowledge of PDFs is necessary to understand how ion and electron beams propagate within real-world systems. In this installment, we’ll discuss the concepts of phase space and emittance as they apply to the release of ions or electrons in beams.

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Christopher Boucher September 15, 2016

In this blog series, we’ll investigate the simulation of beams of ions or electrons using particle tracking techniques. We’ll begin by providing some background information on probability distribution functions and the different ways in which you can sample random numbers from them in the COMSOL Multiphysics® software. In later installments, we’ll show how this underlying mathematics can be used to accurately simulate the propagation of ion and electron beams in real-world systems.

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Caty Fairclough July 25, 2016

Quadrupole mass filters, the key component of quadrupole mass spectrometers, filter ions by their charge-to-mass ratio, only allowing ions with a certain ratio to pass through the device. As such, a high transmission probability for a specific ion through the filter is desirable. However, fringe fields in the mass filter can affect this probability. By using multiphysics simulation, we can take a closer look at quadrupole mass filters and investigate the effect of fringe fields on these devices.

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Christopher Boucher June 8, 2016

Static mixers are well-established tools in a wide variety of engineering disciplines due to their efficiency, low cost, ease of installation, and minimal maintenance requirements. When evaluating whether a mixer can be used for a certain purpose, it is important to determine whether the resulting mixture is sufficiently uniform. In this blog post, we will discuss the setup of an app designed to quantitatively and qualitatively analyze the performance of a static mixer using the Particle Tracing Module.

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Fanny Littmarck December 2, 2015

Healthcare-associated infections (HAI) affect millions of people around the globe. While the most common cause of HAI is direct contact with the source, airborne bacteria may also play a role in patient infections. To prevent airborne infection and make hospital clean rooms safer, it’s important to design efficient ventilation systems. As an added benefit, efficient ventilation designs also lead to lower energy-related costs. The first step to a better design is CFD modeling.

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Daniel Smith November 19, 2015

Many different tools are available for counting particles. Choosing the optimal method depends on the application; specifically, whether you want to use the number of counted particles in equations or during postprocessing. The Particle Tracing interfaces in COMSOL Multiphysics feature three main particle counting options. While these approaches are versatile enough to compute quantities such as charge density and momentum flux, our focus here will be computing the number of particles on a set of domains or boundaries.

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Bjorn Sjodin January 23, 2015

How can you use an electric field to control the movement of electrically neutral particles? This may sound impossible, but in this blog entry, we will see that the phenomenon of dielectrophoresis (DEP) can do the trick. We will learn how DEP can be applied to particle separation and demonstrate a very easy-to-use biomedical simulation app that is created with the Application Builder and run with COMSOL Server™.

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Bridget Cunningham December 16, 2014

Charge exchange cells are often used as a way to obtain neutralized beams of energetic particles. In this blog post, we introduce a model of a simple charge exchange cell and analyze its neutralization efficiency.

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