Upcoming Webinar on Particle Tracing Simulations
Lexi Carver January 10, 2014
Charged particles (such as ions and electrons) are susceptible to electromagnetic fields that exist in the space they occupy. Macroscopic and microscopic particles (dust, pollutants, etc.) are primarily susceptible to forces due to the background fluid (liquid or gas) in which they reside. Particles may also interact amongst each other, or influence the surrounding fields. For systems such as particle accelerators, aerosol distributors, and filtration devices, it can be helpful to calculate particle trajectories or know where the collisions and interactions occur. In a webinar on January 23rd, you can see how the COMSOL Multiphysics simulation software can be used to compute the trajectory of particles.
Modeling Particle Motion, Trajectories, and Collisions
Particle tracing tools are useful for modeling a variety of applications, including mixing and visualizing flow; separating particles in a medium; evaluating the masses of atoms or molecules, an application called mass spectrometry; focusing plasmas and ion streams; and manipulating and observing beams of charged particles in electromagnetic fields, to name a few. The Particle Tracing Module (an add-on product to COMSOL Multiphysics) is a tool specially designed for computing particle motion as well as the applied fields and forces.
A COMSOL model of a quadrupole mass spectrometer showing ion trajectories. The trajectories are affected by the surrounding fringe fields.
Several types of forces can influence particle trajectories. Electrical forces cause particles to move in either the same direction as an electric field (if the particle has a positive charge), or the exact opposite direction (if the particle has a negative charge). Magnetic fields produce a force orthogonal to the direction of motion, which alters the particle’s trajectory but does not change its energy. Collisions can cause particles to change direction, whether a particle has collided with another particle of the same type or with the surrounding medium. For instance, this can occur in particle accelerators, which are devices that contain charged particles in streams (beams), and accelerate them up to high energies.
Simulating particle tracing is particularly useful for studying many high-precision medical and biology devices — such as electron microscopes that capture images by scanning an area (or object or specimen) with an electron beam. There is a Magnetic Lens model available in our Model Gallery that can be used to simulate the release of particles through the electromagnetic lens that is used to focus the electron beam.
The beam at its narrowest is focused to 10 nm. During this simulation, it is helpful to find the density of the magnetic flux and the trajectories of particles traveling through the lens. These results can help verify the strength of the beam, the accuracy of the device, and describe where collisions and interactions may occur:
Plot of the magnetic flux density in the magnetic lens.
Plot of particle trajectories as they pass through the lens.
Register for the Particle Tracing Simulations Webinar
If you’re interested in learning more about particle tracing and simulation, and would like to get a feel for how to model these applications using COMSOL simulation software, make sure to register for our upcoming “Particle Tracing Simulations with COMSOL Multiphysics” webinar on January 23rd. During the live event, my colleague Christopher Boucher will demonstrate some of the things you can model with COMSOL Multiphysics and the Particle Tracing Module. Also, if you have questions on the topic, make sure to bring them for the Q&A session at the end of the presentation.
Note from the Editor: The live event has now closed. You can watch the webinar in its archived form here.