Diffusion problem with sharp edge
Dear all, Using the 2D general PDE form within COMSOL, I'm trying to solve four coupled differenial equations, in order to obtain the velocity profile of an magnetohydrodynamic flow. One PDE for the...
View ArticleDistribution of concentration of species that depends on velocity field
I have set-up a simple rectangular geometry that consists of a rectangle, an inlet and an outlet. As a flow-medium I use air. Next, I have solved for the stationary velocity field, using the...
View ArticleCOMSOL 4.2a Sloshing in a water Tank
Hi, I just started using COMSOL. I wanted to model the sloshing in a tank of water. I used the tutorial "Sloshing tank" present in the site by modifying the geometry the density and viscosity of the...
View ArticleHow to build a sqaure in 2D axis symmetric geometery
Hello I have got stuck in to very simple problem, I have a built a 2D axis symmetric circular plate to model my inductor and in addition I want to add a metal square late. I have to use to 2D axis...
View ArticleConservation of Mass In Laminar Flow study
Hello, I have constructed a model for which one of the physics is laminar flow. The model consists of two inlets which eventually join together to create on cylinder. This cylinder has several...
View ArticleArrange Continuity between Thin Shells and Solids in an assembly - HT
Hi, according to this older thread: www.comsol.com/community/forums/general/thread/14702/ I finally established a proper simulation of combined thin shells and solids heat transfer (union). But as I...
View ArticleSquare Geometry with Turbulent Flow and Fixed Temperature Walls Help
Hello, I am trying to model a square geometry with air inside and the walls at fixed temperatures. The model I chose was this: Conjugate Heat Transfer --> Turbulent Flow --> k-e model using...
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 Articlenegative index in product of combustion
Hi everyone, Im tryin to simulate combustion in combustion chamber. the fuel is gas pyrolysis (ch4, c2h6, h2, and co) it enter the domain from the bottom of the chamber. i also have air input which...
View ArticleEigenvalue calculation of a dipole antenna
Hello, I built a simple dipole antenna to study the feature of the Livelink for MATLAB. The dipole is built as a 2D axisymmetric structure. Both eigenvalue solver and eigenfrequency solver are adopted...
View ArticleReg: Error encountered in Frequency Domain of AC/DC Module.
Hi, I am trying to model a planar coil in AC/DC module. Initially i ran the model with stationary study step and then i changed it to frequency domain study step. With Stationary study there was no...
View Articleheat and mass tansfer in porous medias
Hello everyone I am trying a problem of heat and mass transfer in porous media. it is a moist environment-based of fibers of wood submitted in a hot pressing operation. the medium is considered...
View ArticleError in solving dispersion relation for 2D Photonic Crystal
Hi, I have been trying to compute band diagram for a 2D photonic crystal similar to the one described in the documentation for ver3.5. I have been working on v4.3a and when I click compute, I face the...
View ArticleSide operator evaluated on edge not adjacent to given boundary number
Hi, I am currently working on acoustic-shell interaction problem and I came across a following error: "Side operator evaluated on edge not adjacent to given boundary number". Could anyone explain me...
View ArticleRadial mode of a disk resonator
I am simulating (both 2D and 3D) a radial bulk mode disk resonator based on a paper. The problem is when I use a non zero poisson's ratio the mode shape becomes distorted. With the same material data...
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 Articletime and space dependent distribution
I want to implement a custom model in COMSOL 4.3b. This model depends on a distribution, which in turn depends on time and space. How can I implement such a distribution in COMSOL? My first thought:...
View ArticleNavier-Stokes Simulation using General Form PDE: The Continuity Equation
Greetings all. I am working to solve a standard fluid flow problem (e.g. flow in a pipe as a start) using the General Form PDE interfaces instead of the Fluid Flow built in GUI. I am able to define a...
View Articlecannot use old values as the initial values for new step
Dear sir or madam, I am using comsol to simulate a stationary model. I had convergence problems so that I was forced to vary the inlet BCs gradually to converge to the real case and I had to use the...
View ArticleDecyphering 'Axis Vector' error
When I attempt a Frequency Domain solution I get the following error message: "Errors during multiphysics. Two points describing the axis vector needs to be defined properly. " I can't find a reference...
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