No convergence. Relative timestep too small. Double dogleg solver.
Hello, I am trying to use Double Dogleg Solver for a Navier-Stokes problem, and even tough the residuals in the convergence plot have reach 100% for the velocity and pressure segregated step, I get the...
View ArticleShape not in interpolation curve not preserved
I'm using an interpolation curve as a way to import a 2D geometry into my model. Figure1 shows the shape of the data I wish to import (as shown in Excel). However when I import this data, saved as a...
View ArticleRecoverable error in residual, but solver could not recover.
Recoverable error in residual, but solver could not recover. What is the meaning of this error ?
View Articleregarding the error occured during simulation
Iam designing RF mems switch I got this error while computing Failed to find a solution for the initial parameter. Segregated group 2 System matrix is zero. Returned solution is not converged. Kindly...
View ArticleCOMSOL Releases COMSOL Multiphysics version 4.3a
We at COMSOL are proud to introduce version 4.3a of COMSOL Multiphysics to the COMSOL community See: http://www.comsol.com/products/4.3a/ This introduces: * LiveLink™ for Excel® * LiveLink™ for Solid...
View ArticleEstimated error in the energy norm OR the error norm.
Hello everyone, I am having trouble with something that I can't seem to find any help about in COMSOL support. I only see it mentioned very little and not in very much detail in the help documents. I...
View ArticleHow do you know which resonant frequency of the cantilever is the proper one?
Hi, everyone. I'm quite confused. It's a rectangular beam,with one end fixed. Then I do the eigenfrequency study. When I apply different mesh method to the beam, for example, first I use Free...
View ArticleDimension of a exported data array
I have two model, and I need to graph with matlab the difference. I plot with 1D graph a first model, and export the graph; then i plot with 1D graph the second model, and export the graph. My problem...
View ArticleMagnetic Fields, No Current
Hi everyone, So I've been trying for a while now to bypass the problem of creating an external magnetic field in *other* AC/DC modules; but now I see that in the MFNC there are two options: External...
View ArticleCalculation of electrostatic forces
Dear all, I have a querry regarding electrostatic force calculations in comsol 3.5(a). According to the manuals and few tutorials on calculation of electrostatic forces in MEMS module, it seems to me...
View ArticleError : Failed to find consistent initial values
Hi ! I'm trying to simulate a magnetic dipole in time domain but I'm encoutring an error. The model is fonctional in frequency domain but when I use the time dependent study, the progress window shows...
View ArticleFrequency Domain Study
Hi, I'm starting to use Comsol and I'm trying to do a frequency domain study on a poroelastic material subject to a sinusoidal load which frequency is in the range 1 to 100 Hz. My problem is that I...
View ArticleSphere-Sphere Forces
Hello. Firstly, greetings to everyone, I am new here. So, I am trying to build a model based on this article:...
View ArticleEigenvalue analysis " Mass matrix is zero"
I am trying to run a Static Eigenvalue analysis of a structure . My model is a stone-building , so i just enter the properties of the material and the constraints . When i solve the problem appears the...
View ArticlePoroelastic waves - acoustic module - material definition
Hi, I would like to model a poroelastic material with the acoustic module. However, can you tell me how I can link my parameters to material proporties. My parameters are : - porosity - tortuosity -...
View ArticleNewbie needs help seting up ramp function as voltage source
I am new to comsol and cannot figure out how to assign a rect function as the input source to a strip of copper. I subsequently need to study the thermodynamics (which I have successfully done in...
View ArticleVery strange displacement values for eigenfrequency calculation of...
I am modelling a piezoelectric cantilever beam using the piezoelectric devices module in 4.2a. For certain beams, which have several piezoelectric elements on one beam, I get a very high value for the...
View ArticleTemperature Depdendent Electrical Conductivity acting weird.
Hi Everyone, I have two simple questions that I have been unable to answer after trying to work on them for a week. Please help me: 1) I have a very simple model (which I have attached), I am passing a...
View Articledifferent results of simulating mechanical resonant frequency
I am trying to simulate the longitudinal (x axis) mechanical resonant frequency of a free standing beam. I set the constrain at y and z axis and did the simulation. However, even I keep every...
View Articlecapacitance of a parallel plate capacitor
These are the steps for my capacitor simulation 1. set two solid blocks (dimensions (25x1x20) ) 1 distance away from each other. 2. set a solid box (65x43x60) to surround the plates of the capacitor....
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