Defining dispersive material
Hi, I need to define a material that has Eps Real = 1 and Eps Imag = 2 at 0.1 GHz. How do I fit a 1st order model for this material? I have uploaded a screenshot of the dispersive curves for this...
View ArticleConcentrated Chemical Species
Hello All, I am in trouble defining the constraint for the dependent variables (mass fractions) in Concentrated Chemical Species physics. I have the mass fraction of Species A to E and one inert (total...
View ArticleGeneral question regarding dimensionality in Comsol
Hi, I'd like to ask a question about mixing problems of differing dimension in Comsol. My interest in this question comes from electromagnetics, but I think it could be useful in many areas and I...
View ArticleRegarding structural mechanics module
Hi all, I can see only solid mechanics and poroelaticity in structural mechanics module in add physics.Can i add more modules to structural mechanics module.If so ,please tell me how to do it?
View Articlemagnetic concentrator
Hello, I work on a cold crucible for the fusion of silicon with a coil around (around 10 kHz). I have done a 3D model of the crucible to know the efficiency of the crucible (how power is transmetted to...
View ArticleLooking for someone with comsol experience for a comsol job
I need some comsol models to do in the next month. I don't have the time and experience to finish all so I am looking for some help. This is like a job project if someone is interested. The simulation...
View Articlejava.lang.RuntimeException: Expression is not consistent with previous one
Hello, I am new at comsol and at the moment am having trouble generating solver sequences from a study in a RF module of Comsol 4.0. I have defined a simple geometry which can be varied by Parameters...
View ArticleParametric Cutlines and Exporting of Data
Hi, I am currently solving a parametric sweep problem where I am varying a geometry parameter. I wish to create a cutline on the geometry which depends on this. Currently I have my cutline defined with...
View ArticleSolving a system of coupled PDE
Hi, I try to solve a system of coupled PDE with Comsol. Unfortunately, I have problems to choose a suitable solver. Details of my question and a model file are attached. I would be very grateful for...
View ArticleIncorporating Lagrange Multipliers
Hello again, Thanks to the help of those on the forum I was able to incorporate weak constraints to get accurate flux calculations in my diffusion models. However, I am trying to understand how exactly...
View ArticleOn microstrip impedance computation
Hi everybody, I'm a very beginner COMSOL user, I started just some few days ago with the 4.3a version and I need to build some microwave sensor models. I started trying to realize some very simple...
View ArticleBH Curve as function of normH and T
Hi, I'm study the induction heating of a billet and I'd like to implement a BH curve as function of normH and the temperature. I have an analytical formula for that where I compute the normB as...
View ArticleVelocity Profile with Gas Absorption or Combstion
Dear all! I am wondering if it is possible to link the velocity profile of a gas flow to its concentrations, or partial pressures. For example, if you have 10% NH3 in air and you're scrubbing it with...
View ArticleHeat transfer through a helical structure.
I am currently working on a model where I am trying to estimate the total heat gained by a cold liquid passing through helical pipe with a rectangular cross section which is being heated by a gas...
View Articlesoil plasticity in poroelasticity
I am doing a project using poroelasticity interface, but I wan to consider plasticity behavior of porous materials, so I need to use plasticity constitutive model for porous materials. How do I add...
View Article3D and 2D integration from the walls of a cylinder
Hello, I need to get integral from the surface of a disk and the walls of a cylinder in 2D and 3D geometries. I am fine with getting integral from the surface of a disk in 2D axisymmetric geometry and...
View ArticleIs it possible to input non-isotropic thermal expansion coefficients for...
I am using Comsol for a small project using solid mechanics physics and was wondering if I could define a coefficient of thermal expansion as diagonal instead of just isotropic for a hyperelastic...
View Articlesolution of Navier-Stokes equation for shear modulus reconstruction
Hello I am solving Navier-Stokes equation for shear modulus estimation with comsol and livelink for matlab. The equation i have to solve in comsol is ∇.μ∇u+∇(λ+μ)∇.u=0 But i can not find this form in...
View ArticleTrouble with Livelink-tutorial
Hello, I am trying to set up the busbar example taken from the 'Introduction to LiveLink for MATLAB'-PDF. I am using Ubuntu 12.04, MATLAB 2013a and COMSOL 4.3a. I am able to proceed until mphgeom() is...
View Articlesimple tissue ablation model
Hey all, Im trying to set up a very simple ablation model of cardiac trouble and am having trouble
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