Resonating magnets
Hi folks, Me and my team-mates are working on a project and we now need to simulate a design we made. We have a tube with a length of 10cm and a diameter of 2cm. At both ends of the tube, say x = -5cm...
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 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...
View ArticleSimulation time for 2D and 3D vastly different (with comparable DoF)
Hello, I have a question regarding relative simulation time for 2D and 3D structure. I am using COMSOL RF module to simulate an optical structure. When I try a 2D case with very fine mesh density and...
View ArticleParametric sweep and geometry change
a,b,theta_a and theta_b are global geometry parameters. theta_a = 2/a, and theta_b = 2/b. a,b,theta_a, and theta_b are all used in geometry creation. I am running a parametric sweep for parameters a...
View ArticleDiscrepancy between particle trajectory and streamline?
Hello, I'm trying to teach myself how to use the particle tracing module, so I'm modeling a simple T-junction microfluidic channel. I get an unexpected result, however, when I trace the particles....
View ArticleParameters calculation
Hello, I would like to ask if anyone know where I could find a full list or a list of the parameter comsol calculates when solving a model?. For example I know for piezoelectrics Y11 corresponds to the...
View ArticleInitial Conditions for Sine-Wave or More complex disturbances
Hi Everyone, I have reviewed previous posts in Comsol forum about I.C . One of the suggested ways of applying the I.C was to do a stationary analysts before the time-dependent one. (This can be true...
View Articletime dependent boundary conditions
hello all.. i am solving a time dependent heat transfer problem.. at the start ,for a rectangular domain boundaries 1 and 2 are insulated and 3 and 4 are assigned with constant temperature.. after some...
View ArticleHow to integrate a table result
Hello, I have calculated surface integrals for total flux over particular features in my geometry. This outputs a table of total flux in (mol/s) vs. time points. I would like to then be able to...
View Article2D geometry but illuminated from below
Hi, I want to create a 2D geometry but illuminate it from below, or out of plane, with a plane wave. Whenever I try and set the Background Field as exp(-i*emw.k0*z) (in x direction) I get errors as it...
View Article2 sets of PDE equations with same variable
Dear all, I have a Comsol model in which I have two almost identical sets of general PDE equations. This is because i first solve them with a stationary solver to find stable initial conditions and...
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