Two tolerance factors for segregated solver?
Hi, everyone:I am using the segregated solver to do a time-dependent simulation. I found there are two settings for the tolerance factors: one is in the general setting of this solver, and the other is...
View ArticleMagnetic Field Formulation model won't converge
Hello,I am quite inexperienced with COMSOL and am trying to simulate the influence of an aircraft's body on the geomagnetic field. I have done several simpler models on this, which have worked. But my...
View ArticleUnexpected deformation when exported the result geometry
When I finished the fluid solid coupling, I tried to remesh the deformed configuration. Here comes the question, when I export the mesh of the initial time, it is supposed to be the exactly same with...
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Homogenization: Implement a "change of argument" for a dependent variable
Dear all,I'm a beginner on COMSOL and I have some problem on the definition of variable.Indeed, I try to model a scaling problem by the homogenization theory (expansion asymptotic). I see how to...
View ArticleElectrostatics on a thermally expanded or contracted model
Good mornign everyone,I am currently investigating the electric field distribution on a cable termination and would like to perform the following analysis:Calculation of electric field at initial state...
View ArticleError with dynamic probes using General extrusion
Hi, I am trying to use the same for droplet evaporation. I need to obtain a whole bunch of data in the variables section, eg., Mass fraction, Density and others. I defined a general extrusion operator,...
View ArticleDetermination of Sensitivity co-efficient of a PCF structure
I want to find relative sensitivity co-efficient of PCF structutre. It can be defined as, r=(nr/ne)f where, nr represents the refractive index of the material to be sensed, and ne is the modal...
View ArticleConstraint: Integral of Current Density
Hello everyoneI'm trying to solve a 2D simulation where I'm interested in the induced currents in a certain domain.However, in 2D, due to the asymmetry of the problem, the induced currents in the...
View ArticleParticle tracing in magnetic field
Hi,I have a radially symmetric magnetic lens. I want to simulate how input particles (with xy distribution and certain velocity) go through the magnetic lens and what is the distribution. I used...
View ArticleInifinite boundary
Hello ,I am working on a model (2D) where i am moving the charges produced by an HVDC conductor in space. I would kindly like to know how can i make the boundaries as inifite so as to keep the charges...
View ArticleElectric insulation doesn't work
HiI want to simulate a beam with a silicon layer and a metal layer. Joule heating on metal layer, and I want to see what happens on silicon layer. So I gave a electric insulation surface between them....
View ArticleNegative concentration values - transport of diluted species + Darcy's law...
I run my model and it works. However, I obtain negative concentration values. It is a model related to the hydrogenation-dehydrogenation of a hydride bed. I have experimetal thermodynamic parameters...
View ArticlePiezoelectric energy harvester
HiI am doing a project based on cantilever type piezoelectric energy harvester. I have done the Eigen frequency analysis and Frequency domain analysis. The graph for electric potential versus frequency...
View ArticleThin Imptermeable Barrier Boundary Layer in Coefficient Form PDE
Hello everyone,I am working on a diffusion model but the reaction terms require me to use Coefficient Form PDE rather than transport of dilluted species. I need the thin impermeable barrier equivalent...
View ArticlePull force of a permanent magnet on an iron sheet
Hi all,I am currently trying to model the pull force of a permanent magnet when attached to the surface of an iron sheet.I have currently used the 'force calculation' in the mfnc set up, and I am...
View ArticleNested geometries
Hello. I am trying to create a model in which there is a cylinder containing two ellipsoids, which are contained within each other, one being larger than the other. The larger ellipsoid is s1 and the...
View ArticleImplementing Dirichlet boundary condition using weak constraint
Hello everyone.I am trying to solve the Laplace equation on a square with Dirichlet boundary conditions. I would like to know if it is possible to implement the boundary conditions using the weak...
View Articlecalculation pressure in 2d and 2d-axi
Hi, all I need calculated the laplace pressure in water flow system. I simulate 2d and 2d-axi example However, the pressure values are different, although, both have the same mesh size, equations,...
View ArticleCreating separate subdomains
Hi,I'm fairly new to comsol and am currently having a bit of trouble creating two separate domains within the same geometry for a fluid flow problem. I'm working with a simple two dimensional geometry...
View ArticleNonlinear Frequency Response
I am interested in modelling the effect of geometric non-linearity on the frequency response of a resonator. However, most of the problem seems to be linearised. I am trying to generate a nonlinear...
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