Comsol does not finish the calculation even though convergence criteria is...
Hi, I have a rather strange problem with COMOL and hope that anyone can help me. I am trying to solve a "free and porous media flow" on a 3d geometry. The calculation is not converging very well but it...
View ArticlePML only available to Frequency response analysis?
According to the following paper, PML was available only for frequncy response analysis and not implemented in eigenfrequency analysis in COMSOL 3.3. But is this still the case for 4.3a...
View ArticleAcoustic S Parameters Calculation
I am having some difficulty in calculating the acoustic S parameters in COMSOL 4.2a. 1) What parameter should be measured to calculate the S Parameters? Should it be the acoustic pressure [Pascals] or...
View ArticleAcoustic S Parameters Calculation
Hi, I have a very beginner-level doubt regarding the understanding of S Parameters- If we are to take the scattered sound pressure values, they have a real and imaginary part, i.e they are in the form...
View Articledual core effective index
Hi everybody, I want to calculate the effective indices in two cores of a dual core PCF separately.When I run the programme, light is confined in both cores simultaneously.I want to calculate effective...
View Articlewhat are the 'sweep'- 'motion of cross section' parameter bounds?
I am trying to create a helix which changes cross section throughout its length. I have managed to get it something like i am looking for but need to know how the parameter s changes along the path of...
View ArticleHow to modify element type in comsol 4.0?
I used weak-from PDE a lot for custom physics simulation purpose. In comsol 3.5a, you can set the element shape function type and its order or even specify discontinuous element type in 'Element' tab...
View Articlesingularity. error
Hello, Does anyboday know why I encounter the below error message in Comsol 3.5a? Error: Time 7.86913096623935e-007: Repeated error test failures. May have reached a Last time step is not converged....
View Articlesimulation of solidification or crystallization using Phase-field method?
I didn't find examples in the model libraries that can be referd to. Does anyone can recommend some references to me to read about how to simulate solidification using the phase-field method in COMSOL?...
View Articleanode and cathode
Hello everybody! I'm creating a plasma with a Inductively coupled plasma and laminar flow interface. I want to put the electrodes (anode and cathode) in the model (within the device) and apply voltage...
View Article3D optical waveguide error
Hello everyone, What I'm trying to do is basically simulate an optical fiber in 3D. I thought it would be a simple task but I'm running into an error. I created an optical fibre with an air cladding....
View ArticleIntegrate one Study in another
I am trying to solve a study with a fluid flow problem and an electrochemistry problem. Both studies can be solved by themselves but if I want to solve them together or use the Velocity field of the...
View ArticleError in the demo model ?
There is a demo example "Thermoelectric_leg.mph" available in the Multiphysics installation and it locates in directory c:\program files\COMSOL\COMSOL43b\demo\builder\thermoelectric_leg.mph". It uses...
View ArticleNavier-Stokes Simulation using Coefficient Form PDE
Hi: I need to simulate fluid flow in a triangular duct, but I need to run it on a high reynold number. The problem is that when I run the model using the default "Laminar Flow" physics tab, I need a...
View ArticleLocal current density
Hi, I am working on a simulation of a redox flow battery. I used the redox flow battery model COMSOL provided and edited it a little. I don't understand it fully and what puzzles me the most is that...
View ArticleContact Force
Hi, Does anyone know how to simulation contact force in COMSOL 4.3a MEMS module? I am trying to simulate a electrostatic actuated MEMS beam which will make a contact with contact electrode when...
View ArticleHow to connect a COMSOL model between two nodes of a circuit?
How to connect a COMSOL model between two nodes of a circuit?
View ArticleComsol 3.5a: Simulating Superconductivity with respect to time.
Greetings, I'm a newbie in Comsol using 3.5a. I am trying to model how superconductivity changes in time. I have the proper constants, scaler expressions, and subdomain expressions that I need. I have...
View ArticleSetting up simple optimization problem2
Hi, I'm trying to set up a simple optimization problem. I have a half sphere at the limit between two distinct elastic layers. I have first run my model using a successful parametric sweep to find the...
View ArticleLaser heating of Sphere
I'm currently attempting to model a spherical object that is being heated by a laser. I have defined the laser using a gaussian pulse with the function for the heat flux being: plaser*gp1(x)*gp1(y)...
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