Electric Fields - Insulated Electrodes
Hi all, I am trying to simulate electric field around insulated electrodes and placed inside a cylinder containing dielectric material. Could someone help me setup the model correctly ? I am trying to...
View ArticleLoad materials from library with Java API
Hello COMSOL aficianados, We are working with the Java API for COMSOL here. Let's say you want to load the material copper into your model. It seems, according to the manual, that the only way to get...
View ArticleRichard's Equation questions
Hi, I'm trying to use COMSOL to model water infiltration and evaporation in porous media. Few questions in this issue: 1) How do I define a boundary as open boundary for Evaporation. How do I define...
View ArticleGlobal constraint
Hi, I am modelling thermodiffusion of moisture with the mathematical module. Is it possible impose a constraint to the concentration, c, in order to ensure it stays positive.
View ArticleAssigning material properties to an interior volume
I want to assign the empty volume within a closed container to be a fluid and assign material propertied to this fluid. I imported a closed 3D model that is made up of a number of solid parts contained...
View Articlehow to simulate a permanent magnet with vertical movement toward a coil ?
Hello everybody, i want to simulate a permanent magnet with vertical movement toward a coil i've used magnetostatics and moving mesh in comsol 3.5 i defined a constant Br(remanent flux) and a...
View ArticleBC in assembly mode
hello, idk but i am getting an error in running the simulation. I am getting a warning saying: "MUMPS allocation factor increased to 1.44". What does it mean? is it due to the insufficient BC? I am...
View ArticleHow to see the plots after running in batch mode?
Hello! I managed to get comsol to run in batch mode (Linux). However, after I open my newly created output model file out.mph, I do not see any graphs available. I am solely interested in CFD module,...
View Articleparticle deformation througn a contrained channel
Hi there, I am doing COMSOL simulation to see the behavior of a particle flow through a microchannel. There is a area of the channel where particle size is greater than the cross section. So the...
View ArticleModulated sinusoidal excitation
Hi everybody, I have to simulate a piezo transducer. The excitation of ceramics is a modulated sinusoidal excitation with an amplitude of 110V. In Piezdoelectric Devices module, I just can set a...
View ArticleExternal U vs. I
Hello, I'm quite new to COMSOL. I generally have doubts where to use external U vs. I or external I vs. U when I want to insert my designed model into a circuit. I think in any of those cases I have to...
View Articlehill plasticity
Hi, Trying to make hill plasticity non-symmetric so my question is; is it possible with different yield stress level in tension and compression. Then in addition the plastic stage is confusion. How are...
View ArticleTaking Coriolis into account in Solids mechanics
Hey, I'm trying to implement a coriolis force thanks to a body load. For a rotation around the axe Z, I'm using the following expressions : 2*omega*solid.rho*vt -2*omega*solid.rho*ut 0 My case is on a...
View ArticleFluiddynamics with Magnetic Fields
Hello, I have few questions about the modules. First the explanation of my problem. I have fludic magnetic metal and this metal flows through magnetic field. To simulate this I wanted to combine the...
View ArticleParameter studies.
Hi I am trying to do parameter studies of the device and find the design variable that is important. In order to do, I am simulating 5 cases at one time, but I guess this makes the computer go crazy....
View ArticleMesh continuity at boundaries
Hello, I'm starting with Comsol, and I have this question, that may sound really basic to many of you. I have defined a contact pair between two parts of my geometry - an assembly. Now I would like to...
View ArticleParticle trajectories
Hi I am trying to +vely charged massive particles being accelerated through a tube. They then hit a dynode which creates photoelctrons which in theory should propagate perpendicularly to the incoming...
View ArticleDefinition of diffusion coefficient function
Hi I am trying to model the drying of a cylindrical part by using the "transport of diluted species" module. In this model, I specified the temperature dependency of the effective diffusivity...
View ArticleOptical coupling between laser wave-guides and optical fiber
Hello Everyone, First of all, I am a beginner to use this software and getting to know this from the tutorials posted. I am trying to model 'Optical coupling between laser wave-guides and optical...
View Articleerror "cannot evaluate expression"
Hi, there is an error information when I solve two 1D-PDE models in comsol. How can I solve it? Thanks a lot. By the way, I don't select any material, since the value of the solutions mean density...
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