Performance problems with Interpolation Function
Hello, I am using a 3d interpolation function with data from a large file (>100MB). When I execute a computation (e.g. an Eigenfrequency Analysis), it takes a long time (~15 min) before the solver...
View Articleheat transfer coefficients
I'd like to know more about the heat transfer coefficients present in the material library. I see that it depends from the surface temperature, from the temperature at infinite distane and from a...
View ArticleAnalytic function accepts only [m] and not [mm]
Dear all, I have a trouble using an analytic function: I get values only using the SI unit of measure, and not with the MPa one. The model is a first attempt of a welding simulation, and the analytic...
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 Articleunit normal vector
Hello, I am solving a PDE using coefficient mode. I have a scalar filed, variable C, which has arbitrary boundary inside the domain (picture 1) that evolves with time. I want COMSOL to find the unit...
View Articletime dependent load
Hi all, step by step I'm improving myself on Comsol. I have just a little problem with "time". How can I make a time dependent simulation with a random function included, for instance, a force. I know...
View Article3D AC/DC simulation with motion? COMSOL 4.2a
Hello, I would like to model a 3D permanent magnet generator moving at a constant rotational velocity. My plan would be to use the AC/DC module combined with the Structural Mechanics>Solid...
View ArticleHow to couple pore water pressure to simulate triaxial test using Cam-clay model
Here are some questions I want to ask. Thanks! the figures are in doc file. Problem description: We want to simulate the behavior of soil sample from a trialxial test. The cam-clay model here is...
View ArticleHeat source: Temperature profile instead of heat
Hi, I want to use measured values to define a heat source in the "Conjugate Heat Transfer". I could already generate a 3D-function of these values which can be used as Q. But my problem is that the...
View ArticleDefining 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 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 Articlehow i can to calculate the electrostatic force and couple it to two phase...
hi i want to Simulate Heat Transfer Coefficient and Hydrodynamics of Single Droplet Affected by Electrostatic Fields. how i can calculate the electrostatic force and couple it to two phase flow- level...
View ArticleAC heat generation
Hello, I try to convert the “Hepatic Tumor Ablation” from the Comsol library, which uses DC current and Bioheat transfer, into AC current and Bioheat transfer. Until now the electric field distribution...
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...
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