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 ArticleDifficulties with #985 Peristaltic Pump Model
Hi All (bear with me; I'm new) Working my way through the peristaltic pump tutorial and all has been a-okay thus far but once I get to the plot of the total volume (bottom of pg. 14) when I try to...
View ArticleHi: need help on electro-rotation studies
Hi I work on electro-rotation studies through dielectrophoresis(DEP). Problem involves lot of variables, however I would like to know a way to obtain rotational simulation due to DEP? Currently we got...
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 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 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...
View ArticleDrude Model in Transient Simulation
Hi, I am trying to simulate in time domain the propagating wave along a metal/dielectric interface, where the metal permittivity is following the drude model. The way I approached that problem is that...
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