Definition of "Port" as a boundary condition
I want to understand the definition of "Port" as a boundary condition in RF module. Typical problem for setting Ports are shown in attached files (plasmonic_wire_grating.mph and...
View Articlecoupling of physics
Hi, I'm trying to use the voltage (electric potential) output of piezoelectric physics as an input (voltage) to the semiconductor physics. i don't know how to pass the voltage from piezoelectric...
View ArticleMeshing a twisted wire
Hi, I'm trying to model the flow of current in a twisted wire. The inner rods are of steel, the outer of Al (see attached file). The steel rods are twisted clockweise, while the Al rods are twisted...
View ArticleFunction for total spring constant in thin elastic layer
Hello, i'm a relatively new user with comsol, specially with the solid mechanics module. The goal in my work is to simulate the interaction between epoxy and fiber glass. I started with a 2D-model...
View ArticleCouldn't plot 2d drawing
This is N.Kumar from IIT MADRAS, I was trying to get the 2d plot for the electromagnetic flow meter.in this regard i was facing the preoblem as, failed to evaluate variable: variable:spf.U Geometry:1...
View Article3D rotating disc problem
Hi I want to a 3D rotating disc simulation in COMSOL 4.2 ver. How can I do this simulation? For example, I want to rotate a disc about 1000 RPM. At 'Initial Values' in 'Solid Mechanics(solid)', the...
View Articlecoupled application
This is kumar,can anybody help me to implement the coupled application about electromagnetic flow meter to solved the flow rate analysis- for analysis this device i have a some clarification also, 1....
View ArticleInternal error in piecewise expression evaluation
Merry Christmas everybody, I was simulating a laminar flow in a heated circular duct with a non-newtonian Fluid. In order to describe the dynamic viscosity I used the non-newtonian power law with the...
View ArticleDrift-diffusion solution wihtout using Plasma module
I want to use comsol to solve drift-diffusion and Poisson equation in a coupled manner for a wire that has variable resistance (or charge density) across it. Charge density at each location depends on...
View Articlesquare pulse train
Hello Everybody, I am trying to make a square pulse train in Comsol without Matlab. The train should have a period of 0.01s, but the pulse itself is just 8e-9s. One pulse is no problem with the smooth...
View Articlemagnetic field gradient in 3D return zero!
Hi everybody If anybody knows that why the gradient of magnetic field in 3D models is always zero? I checked the different methods. for example I wrote d(Bx,x) or different component of B and H. Even...
View Article4-Coil System
Hi all, I am new in Comsol and I'm trying to model a 4-coil system consisting of Source coil, Transmitter coil, Receiver coil and Load coil. Basically, there will be a voltage source supplied to the...
View ArticleExporting Far-field Polar plots data
I would like to export the Far-Field Polar plots data. When I tried to export , I cant plot similar to Polar plots in COMSOL. Any suggestions. It will be really helpful. Thank you.
View ArticleJoule heating simulation problem
Hi I am doing joule heating simulation for a thin surface to generate high temperature. I applied 120V to a thin film but the obtained temperature was not high enough. I found that the temperature...
View ArticleDefine concentration convective flux
Hi, I am a bit confused! I run the model with COMSOL 4.0, i can not find Concentration convective flux for boundary condition. in old version I could find convective flux. do you know where it is!? Tanx
View Articleproblem defining variable function to obtain strain value
Hi, currently i am trying to calculating strain by using this formula in structural mechanics module 4.0 comsol. I am not able to get the strain value. The only value i get is the intop1(1) but comsol...
View ArticleSimulation of a floor heating
Hi all, I want to simulate a floor heating in a 2D modell. Floor heating systems release about 90 % of heat in the form of radiation and about 10 % in the form of convection. So is it possible to take...
View Articlequadratic Mesh
How can i to do a mesh with element quadrilateral quadratic 8 nodes? What the better V4.2a or 4.3 , or other to do the mesh. is it possible export matrix coordinate and topological? . In V.3.5a it is...
View ArticleMy biggest wish for X-mas: Solution for crack modeling
Dear Comsol gurus, dear support, my biggest wish for X-mas was, that the new 4.4 release would finally provide some reasonable approach for crack modeling as being standard in other software packages....
View ArticleDisplacement variable
Hello, I'm confusing in getting displacement of resonator. Can anyone please tell me what's difference between u and pzd.disp variables?
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