Adaptive mesh refinement within a parametric sweep
I am trying to solve a fluid flow problem over a range of inlet flows using a parametric sweep. The solution does not converge at higher flows, so what I would like to do is run the sweep until it...
View ArticleVibrationg structure in fluid
Hello Everyone, This is my first project with Comsol so I have no clue about what I am doing really. My questions are most likely very simple/stupid I'm sure anyone here can help me. What I want to do...
View Articlepower outflow, time average mwp.nPoav
Hello, using a 2D-axial symetric model in rf-module (plasma), on my coaxial power input port I put 50 W.. inner diameter 8mm, outside 50mm (21 mm radial distance). how does mwp.nPoav come on -800 W/m ?...
View Articlecomplex relative permittivity
I need to enter a complex relative permittivity into material settings - can I do this and if so, how? The value is -9.96+0.82i. Many thanks.
View ArticleCOMSOL 4.2a with MATLAB (COMSOL 3.5a compatibility) error
Hi, I'm trying to use COMSOL 4.2a with MATLAB (COMSOL 3.5a compatibility) and I obtained the following error: Undefined variable "com" or class "com.femlab.jni.FlNativeUtil.ensureLibIsLoaded". Error in...
View ArticleDerivative of Interpolation Functions
Dear all, I am trying to understand if, given an interpolation function (defined by a table of points in an external file like *.txt file) it is possible to define the derivative (spatial) of the...
View Articleintegrating a lookup table for frequency dependent variables
Hi everyone, I have created a lookup table for frequency dependent values of epsilon_r. This table includes two interpolation functions: one for the real part (eps_real) and the other for the imaginary...
View ArticleTemperature effect in Electrostatic module.
Hi, I am using Comsol ver 3.5a. Can anyone guide me that how could i observe the effect of temperature on capacitance value in Electrostatic module ? From where i can change/control the temperature in...
View ArticlePlot templates?
Hello, what is the trick to manage all the results coming from different sets of parameters? i run each set into a new mph file. trouble is, when i improve one of the models, i need to correct all of...
View ArticleMultilayer structures: multiple Rectangles or one Rectangle with Layers?
Dear all, I am dealing with multilayer structures, and I have a small doubt: modelling a multilayer, do I get the same results (and of course the same physical meaning) using: 1) different rectangles...
View Articleset path of the external matlab function
Hello all, I am trying to run a Matlab script of my model which in turn uses an external Matlab function. When I run the model from matlab, comsol opens a new Matlab process and tries to call the...
View ArticleWhat does R_const represent?
Hello all, Perhaps this is a silly question, but I cannot find the answer anywhere so I will ask anyways! What does R_const represent in comsol? I cannot find what it means but it is used in a library...
View ArticleElectric field not adjusting with moving mesh
Hi, I have created a model which is effectively a capacitor with a moving plate. I have ground electrodes on the fixed top plate and +/-100V electrodes on the bottom moving plate. I am using ALE with...
View Article2D AC Coil Setup for Magnetic Induction Tomography
Hello, I have managed to create a simulation of a coil in 2D, using just a magnetic field source, however I would like to replace this with a frequency dependent magnetic field. How would I do this?...
View ArticleSolidworks model meshing issue
I created geometry of a saddle coil pair in Solidworks and then I imported it to COMSOL using the geometry import option. When I build meshes, it gives error of meshing around edges and corners. COMSOL...
View ArticleTime Steps
While simulating our case, we have used strict time step with maximum as 1800 seconds. But still, it is taking a time step of 0.1 sometimes. This is making our simulation quite slow during the middle...
View ArticleConvergence Problem: Error smaller than Tolerance
Hi everyone! I am trying to model non-isothermal, reactive fluid flow in a channel with catalyst-coated walls. Therefor I couple the "Transport of Concentrated Species"-module with the "Non-Isothermal...
View ArticleComsol 4.2a Java error with Mac OS X 10.8.3
Hi every body, I am coming back with my "unexpected error". It seems that it should coming from Java. I am working under Mac OS X 10.8.3 and with Comsol 4.2a It appears an expected error with the log...
View Articlefailed to generate mesh for face
hello, i imported a solid geometry to comsol, but when i generate mesh i get error: failed to generate mesh for face, i tried to make custom mesh for these faces, but did not solve the problem. can...
View ArticleDiaphragm
Hi, I am trying to do simulation of air horn diaphragm, Inputs: Diaphragm dia and thickness and material property. Input pressure on diaphragm. Output: Max deflection of diaphragm. Kindly provide me...
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