Relative Permittivity
Dear All, I am performing FE simulation on piezoelectric material. In the material properties section, relative permittivity is provided for both strain and stress charge form. Does anybody know how to...
View Articleinductance
I need to calculate the inductance for a wire (with a arbitrary cross-section) place in a arbitrary tube. That is, an arbitrary coax line. I need to calculate the inductance (both internal and...
View ArticleShape of sessile drop
Hello, I am trying to model the equilibrium shape of a sessile water drop in comsol. I have used a 2D axisymmetric laminar two phase, phase field model for the same. I started off with the shape of...
View ArticleShape of sessile drop
Hello, I am trying to model the equilibrium shape of a sessile water drop in comsol. I have used a 2D axisymmetric laminar two phase, phase field model for the same. I started off with the shape of...
View Articlecylinder roller contact (contact mechanics) modeling problem
My model is pretty simple: a cylinder contacting an infinite half-space and I want to find out the deformation at the contact area as well as the stress distribution in the half-space. Actually this...
View Articlefailed to evalute variable Jacobian"
Hi: I am designing a structure which is gold stripe that is put above Silicon. I am trying to plot the Electric field (y-component) of the resulted mode. The problem is that I did not get the mode. I...
View ArticleDirect comparison to strain gage
I'm modeling a simple fixed-free beam to compare with a piezo strain gage with a foil strain gage that I have on an actual beam (aluminum, 20cm x 2cm x 2mm). I'm trying to decide which strain I should...
View Articlethermal expansion leads to overlapping domains
Hello! I have a model composed of three layers, three different materials, of very different coefficients of thermal expansion. The top layer has cracks built into the geometry. The first two study...
View ArticleTransmitted evanescent compoent after passing through the periodic grating...
Hi everyone, I am folloing the tutorial model about plasmonic_wire_grating. By setting those ports, I can get the transmission and reflection for different diffraction orders T_+1, T_-1 , as the same...
View ArticleGeometry problem "unknown geometry -Tag:null"
Hello! I have done a Chemical Reaction engineering simulation and have synchronized it with a geometry. The fist model I did was too large, so I wanted to create a new one. I have done this by buildung...
View ArticleModelUtil.connect(solverHost, solverPort);
Hi everyone, I try to compair the results of two solvers running in parallel on two different comsol-servers. Therefor I try to establish a link from my Java-API to two comsol server. But only one...
View ArticleComsol not following ideal gas law or conservation of mass
Hello, I am currently working on modeling a high temperature hydrogen heat exchanger. I decided to start as simple as possible and just model the heat transfer into an axi-symmetric tube of hydrogen...
View ArticleWhy does my parametric sweep slow down?
When doing nested parametric sweeps, they start off fast but slow down to a crawl eventually. What am I doing wrong here? Is there a faster way of doing this? Seems it has little to do with my computer...
View ArticleVoltage source in AC
Hi. i'm studing an inductor to analyze inductance and resistence od the model. I use electrical circuit and i work with AC frequency of about 20kHz and i have some questions: 1)Vsrc in voltage source...
View ArticleHeat source
Hi all, I have a model composed of three layers, three different materials. How could I insert a triangular power profile(as heat source) in the second domain. Example of power profile ( t=0s P=0w;...
View ArticleLumped port
Hi, Do i have to use some particular dimension when i use a lumped port? I mean do i have to use a particular hport an wport ratio? Thanks Nicola
View ArticleDependence of Electric field on mesh size in RF modeling
We would like to model our laser in an RF module, solving for electrical field strength, to see the optical field distribution as a function of layer thicknesses, however we kept seeing unexplainable...
View ArticlePlotting in air, postprocessing, 4.2a, RF module
Dear All, I have some issue. I made some calculation of gold nanosphere on substrate, and now I want to plot normalized electric field. BUt, thing is I want to plot emw.norm^2 not just on sphere, also...
View Articlemeshing a cylinder
Hi All, I have been having some issues meshing a cylinder. When you define a cylinder in COMSOL, it splits the curved face into 4 quarters, and as a result, when I went to mesh the cylinder I was...
View ArticleStop condition
Hi all I am running a time-depedent heat transfer simulation. I want to stop the simulation when the average temperature is higher than 310K. i defined Tm as the average temperature in the domain. I...
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