See firsthand how the comsol software works in an interactive online demo tailored to discuss your needs. I use the steps which are there in the tutorial for simulation of helmholtz coil with a few changes. Do the gaugeinvariant physical observables of the theory depend on the specific gaugefixing condition e. Contact comsol, the makers of comsol multiphysics software. In both cases, when meshing these models, automatic mesh refinement resolves the shock pattern by refining around the regions with very high velocity and pressure gradients. Mar 26, 2020 gauge fixing is one of the most intriguing topics in computational electromagnetics. A single model can incorporate multiple physical properties of the system. To do so, you can use the electric currents in shells interface, available as of version 5. The latest version of comsol multiphysics, version 4. The sof tware may be used or copied only under the terms of the license agreement. Warning your internet explorer is in compatibility mode and may not be displaying the website correctly. In addition to this manual, we supply many other resources to help you get the most out of comsol products. Jul 05, 20 gauge fixing for a field now handles magnetic potential and external magnetic vector potential boundary conditions correctly. Comsol installation and operations guide copyright 19982010 comsol ab.
Using a direct solver may be required or beneficial in. Comparison of the computed v field and \textbfe field norm in the coil domain solved without gauge fixing left and with gauge fixing right gauge fixing in the acdc module. I have a em simulation which is an armature in a coil when i solve it without gauge fixing, it works fine and gives me the answer. How to model optical anisotropic media with comsol. Gauge fixing is usually required when the solution of the field is not unique and you want to use a direct solver. For new users of comsol multiphysics simulation software, a proper introduction on how to set up and run a model is essential when learning how to use the software. Wed love to hear from you by phone, email, or web inquiry. Contact comsol official site of comsol multiphysics. Design and optimization of power cable accessories using. Learn how to use comsol multiphysics and the structural mechanics module by conducting a static analysis of a mechanical structure. The result is the same even if the solver needs some more time to solve the problem.
You use the default solver which is created when adding a gauge fixing for the a field in mef physic. The comsol software automatically formulates the energy equation coupled to the momentum and mass balance equations for ideal gases. Accidentally, i changed the model unit and it makes the model bigger. In the acdc module, an addon to comsol multiphysics, there are three physics interfaces that solve for the field. Optimizing planar coils for pcbs with electromagnetics. These gauge fixing methods include lorentz gauge, coulomb gauge and axial. Numerical simulation of the electric field and the study. Comsol multiphysics is a crossplatform finite element analysis, solver and multiphysics simulation software. In addition, you can use this physics interface, along with the magnetic fields interface, to compute the current flow and magnetic field and evaluate the resistance and inductance of. In this blog post, we will present an introduction and background to gauge fixing and then proceed to discuss when and how to use it in the comsol multiphysics software. It allows conventional physicsbased user interfaces and coupled systems of partial differential equations pdes.
When dealing with path integral of gauge field, we use faddeevpopov method and add a gauge fixing term. Electric field of a charged sphere texas state university. Comsol multiphysics alternatives and similar software. Containing a model tree, the model builder outlines the structure of your model. Unfortunately this was not the solution of the problem. This chapter introduces you to the capabilities of the module including an. The gauge fixing for afield feature has added support for using a. I added a gauge fixing for a field item to my magnetic fields physics and selected all domains to it. Filter by license to discover only free or open source alternatives. Note that many of the examples featured here can also be accessed via the application libraries that are built into the comsol multiphysics software and available from the file menu. To excite a microstrip patch antenna fed by a microstrip line to calculate the input impedance and sparameters, as well as to compute the radiation pattern with a far field feature, you can assign a lumped port on the gap between the end of the microstrip line. Comsol multiphysics also has an interface to the matlab technical computing. The software described in th is document is furnished under a license agreement.
On the contrary, magnetostatic simulations are slightly tricky in this case and require the use of an inplane vector solution together with a scalar for gauge fixing in order to obtain the right results. Numerical simulation of the electric field and the study of. In the physics of gauge theories, gauge fixing also called choosing a gauge denotes a mathematical procedure for coping with redundant degrees of freedom in field variables. Voltagedriven multiturn coil now correctly takes harmonic perturbation into account. Using a direct solver may be required or beneficial in cases involving. I have to use this gauge otherwise electric potential is wrong in the model. Comsol provides an ide and unified workflow for electrical, mechanical, fluid, acoustics and chemical applications.
Using a direct solver may be required or beneficial in cases involving multiphysics couplings, as. The comsol desktop 7 the comsol desktop the user interface streamlines the modeling workflow with the model builder. Comsol multiphysics is an engineering, design, and finite element analysis software environment for the modeling and simulation of any physicsbased system. These gauge fixing methods include lorentz gauge, coulomb gauge and axial gauge,etc. It states that any vector field can be decomposed into a curlfree part and a. Comsol multiphysics designed to assist you to solve and model lowfrequency electromagnetics. Computing the solution the program can use the linear order element combination for a coarse solution and solve for the quadratic elements using the geometric. By definition, a gauge theory represents each physically distinct configuration of the system as an equivalence class of detailed local field configurations.
When exciting or terminating an rf device with a specific impedance value on a location where the transverse electromagnetic tem mode is expected, the lumped port feature is useful. Gauge fixing is one of the most intriguing topics in computational electromagnetics. The boundary selection of the uniform lumped port across a slot. Comparison of the computed field and field norm in the coil domain solved without gauge fixing left and with gauge fixing right gauge fixing in the acdc module. Gauge fixing is usually required when the solution of the \textbfa field is not unique and you want to use a direct solver. To help the learning process, there is a streamlined workflow you can follow that is reflected throughout.
I have a problem that you may have its solution and make life easier for me. It is working well without gauge fixing without complex numbers allowed both in 2d and 3d and simulation time is quite fast 0. Comparison of the computed field and field norm in the coil domain solved without gauge fixing left and with gauge fixing right. I added a gauge fixing for afield item to my magnetic fields physics and selected all domains to it. I am trying to create a model to get a magnetic field profile using comsol version 4. Do the gauge invariant physical observables of the theory depend on the specific gauge fixing condition e. Learn how to model the tunneling current across a graded heterojunction in this detailed blog post, which also gives a background of the wkb approximation.
How electric field can be solved in comsol software. Mar 10, 2016 comsol multiphysics software version 5. Learn how to use comsol multiphysics simulation software at a guided training course or webinar. Issues of stranded conductors modelling comsol multiphysics. But when i add gauge fixing it keeps working for ever without answrer. When defining and solving these problems, the fluid is modeled as incompressible by default but can. Alternatives to comsol multiphysics for windows, linux, mac, web, gnu octave and more. Any two detailed configurations in the same equivalence class.
This model uses a design drawn in an external cad software, imports the geometry to comsol multiphysics, and finally calculates the inductance from the specified. I have tried simple cases in 3d, it works the the default solver but the convergence is very mesh. Comsol multiphysics is a powerful simulation software platform for modeling and optimizing the design of any. Comsol multiphysics designed to assist you to solve and model low.
How to model structural mechanics in comsol multiphysics. Creating this geometry inside comsol is complicated because the software. Cfd software for simulating fluid flow applications comsol. Accessing external material models for magnetic simulations. Gauge fixing is usually required when the solution of the \textbf a field is not unique and you want to use a direct solver. How to set up and run a simulation with comsol multiphysics. Iterative solver and gauge fixing comsol multiphysics.
The result is the same even if the solver needs some more time to solve. The evanescent component of the nonparaxial gaussian beam background field is available as a feature in the wave optics and rf modules as of comsol multiphysics version 5. All of the features listed below are implemented through associated physics interfaces. Get a comprehensive introduction to the theory behind gauge fixing.
To download the mphfiles, log in or create a comsol access account that is associated with a valid comsol license. Cfd software for simulating fluid flow applications. The dimensions are in cm and i am trying to do it in frequency domain so that i can pass ac current. Your guide to lumped ports in the rf module comsol blog. Learn about multiphysics modeling and simulation comsol blog. I solve the electric field electrohydrodynamic in one rectangular geometry with one emitter electrode in. Use this installation and operations guide to install your comsol software products and start working with the packages.
To help the learning process, there is a streamlined workflow you can follow that is reflected throughout the user interface of comsol multiphysics. Piezoelectric materials contribute as a key design component in transducers, sensors, actuators, and resonators. Comparison of the computed v field and \textbfe field norm in the coil domain solved without gauge fixing left and with gauge fixing right. This discussion is about an older version of the comsol multiphysics software.
Comsol software users who are onsubscription should submit their questions via the support center for a more comprehensive response from the technical. Units can now be used in the specification of the primitive vectors in the rlc coil group feature. This stepbystep instructional video will guide you through the modeling workflow, with an emphasis on structural mechanics modeling. In the physics of gauge theories, gauge fixing denotes a mathematical procedure for coping. I dont find the sor gauge preconditionner that you talk about. The ability to accurately model these devices can greatly benefit the design process and contribute to increasing the efficiency of the device through better understanding of the multiphysics interaction between piezoelectric, structural, and dielectric or conductive materials in. Installing the comsol software general tips welcome to comsol 3. Mar 24, 2020 gauge fixing is one of the most intriguing topics in computational electromagnetics. Electric field of a charged sphere, brice williams, wim geerts, summer 20, 4 so summarizing, the above shows that the spatial distribution of the electric field given by a solution of poissons or laplaces equations correspond to a state of minimum field energy integrated over the systems volume. Comsol multiphysics package, and they come with their own graphicaluser interfaces that make. The electric field e and magnetic field b of maxwells equations contain only physical degrees of freedom.