Boundary condition setting problem for electrode
Hi! I am using transport of diluted species to simulate particle movement in discharge but have some problems with the boundary condition setting for the electrode: the electron move towards the...
View ArticleDEP particle tracing for fluid flow COMSOL 4.3 simulation
Hi, I've tried to simulate dielectrophoresis by using the particle tracing for fluid flow module of COMSOL 4.3, but I' ve encountered some problems with the dielectrophoresis force. I am trying to...
View ArticleIntegral Boundary Condition - Problem
For the sake of simplicity, I'll use an example of stationary heat transfer in a 2D geometry. My goal was to create a boundary condition such that the total flow of a boundary in the z-direction had a...
View ArticleCOMSOL Error for Initial Values(RF Module)
I am defining a model with different concentrations of oil and water and trying to measure the heat distribution by using the microwaves. But I obtained the error mentioning Initial values: THE...
View ArticleCOMSOL Multiphysics 4.4 is here!
Hello COMSOL Community, The most powerful multiphysics software just got more powerful: We are excited to announce that the latest release of COMSOL Multiphysics, version 4.4, is now available for...
View Articlecoordinates of geometry objects
Hi all! How can I access the coordinates of geometric objects/domains for using in an expression? Alternately: how can I use distance of a domain or primitive center from a plane in an expression?...
View ArticleConvective heat transfer coefficient, h
Hi, Will someone please help me understand the apparent discrepancy I'm noting between convective heat transfer coefficients (h) calculated two different ways using the same input data? For the sake of...
View ArticleCreating Geometry in Autocad for COMSOL - 3dface - surface problem
I have a very complex geometry to be analyzed in COMSOL that can best be modeled by Autocad using 3Dfaces. After composing the model in faces I used the converttosurface command in Autocad, this is how...
View ArticleBulk velocity on parallel lines
Hi all I have a two layer geometry. On the interface for calculation of mass transfer coefficient I need to Reynolds number how that velocity in reynolds relation for any point is bulk velocity of...
View ArticleHow to combine PML and Port together By Comsol 4.3
Hi, I am simulating the surface plasmon resonance. I use pot to set the incident TM plane wave. It looks that there is still some reflection from my port boundary. I want to add a PML to absorb the...
View ArticleMathematical Particle Tracing_Weird results
Hi there! I am posting this thread because I am trying to simulate the deflection of a non magnetic particle in ferrofluids, under the influence of magnetic field. I have simulated the magnetic field...
View Articleerror test failures
hi i use ccp module for simulation,my time range is range(0,5e-5,0.001) but when i compute model times go 7.579247e-019 to this and report this error Repeated error test failures. May have reached a...
View Articleerror: NaN or Inf found when solving linear system using SOR
Hi, I am modeling an aperture antenna structure using the RF module. I keep getting this error. Everything seems well defined in my model: material, boundaries... What does this error message suggest...
View ArticleCOMSOL 4.3-AC/DC MODULE-COUPLED APPLICATION
Hello everyone, I would like to know how i can put the simulation in terms of coupled one which is a combination of Flud mechanics plus magnetic field app.I have to put the moving fluid in a stationary...
View ArticleIntegrate on the cross section to find Moment and Torque
Does Comsol have specialised built in functions to find Moment and Torque by integrating over the cross section of a surface modeled by 3-D elements? Say I model 3-D CAntilever beam in Comsol using 3-D...
View Article[Laser] different layers with different absorption coefficient
Hi, all! I'm an old user of COMSOL but I'm now faced to with a problem. I am usually analyzing thermal profile on two-layered skin tissues using the heat transfer model. When setting up Q_laser as a...
View ArticleModeling swelling using Eqauation based Weak Formulation
Dear all, Hello. I am new in Comsol for my thesis I was working on a model of swelling and frictional phenomenon. I stuck in Comsol. Following are my equations in weak form:...
View ArticleIrregular grating modeling using ports or background field
Dear all, I am a novice at comsol and has been building my first model for some time. I want to calculate the scattered field caused by a plane wave incident upon an irregular grating (with dozens of...
View ArticleFrequency domain study - changing the force on a point load with frequency
Hi, I'm having some trouble finding out how to apply a frequency-dependant force. I have a model where up until now, I've been using a non-varying force of 1N on a point load, then performing the...
View ArticleCalculation of fluid flux
Dear all, in older versions of comsol, there used to be a variable that one could integrate in order to get the fluid flow across a boundary, which was called something like flux (I can't quite...
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