Boundary Mode Analysis Undefined Variable
Simple waveguide problem. I make a rectangular block of air, 2 cm x 1 cm x 10 cm surrounded by the default PEC boundaries. Ports at each end. Ports both set to Numeric. Add study -> Boundary Mode...
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 Articlesome problems in my COMSOL Multiphysics model
Hi There are some problems with my model. I build a model of the RF generator whichis a rectangular cavity and two electrodes and the sample is in the middle of the two plates. The top electrode is...
View ArticleIs the imaginary part of the relative permittivity of Au positive or negative?
Hello everyone. Here is another question about "models. woptics. scattering_nanosphere". In this model, the imaginary part of the relative permittivity of Au is negative, e.g. the complex dielectric...
View ArticleTransmission of rough gold film with different incident angles
Hello, I'm new to COMSOL. And I have a question about the boundary condition of RF module. Hope someone can give me some suggestions. I'm using COMSOL RF module to simulate the transmission of a 3D...
View Articleconfinement loss
Hi is imaginary part of refractive index could be positive or negative that means 1.028175433939737e-19 or -1.028175433939737e-19. I found in my simulation positive and negative values for different...
View ArticleEMW Analysis Methodology
Can anyone offer any specific details on the the Robust, Intermediate, and Fast settings and how they relate to the Mesh and Solver? There isn't much coverage in the reference manuals and guides and...
View ArticleOptical absorption in MIM or MSM plasmonic structure
Hello, I am studying the plasmonic effects on Metal-Si(SiO2)-Metal structure . I try to calculate the total optical absorption (1/m) on the surface of the structure using the Total Power Dissipation...
View ArticleCannot use Prescribed mesh velocity in Frequency-Transient Study
I'm setting up a microwave heating model with a deformed geometry. The microwave field is solved in the frequency domain, and the other physics (e.g. heating) in the time domain. This is accomplished...
View Articlewhat is difference between "Mode analysis" and "Boundary mode analysis" in RF?
i'm not getting , where we should use boundary mode analysis in study step and where we should use only mode analysis in 2D modal.?
View ArticleWhy set the conductivity as zero?
Hello everyone. Here is another question about "scattering_nanosphere". In this model, the conductivity of nanosphere (composed of Au) was set as 0. But its true value should be 45.6E6[S/m]. If we use...
View ArticlePatch antenna with a coat of Microwave absorber
Hi, I am studying the improvement in absorption of radiation by microstrip patch antenna, which is coated with a layer of microwave absorber that I am going to develop. How can I define the physics for...
View ArticleExpress objective function in Optimization study of Frequency domain in...
Hi, I want to run an optimization study in frequency domain. I have experimental values of the variable alpha for specific frequencies and I want to adjust my control variable R in order to match these...
View ArticleMesh size and dimension of the structure
Hi Guys, I am quite new in COMSOL, and I have three small questions about the setting of the mesh in ewfd, frequency domain study. 1. I found the results will be different if I used different size of...
View Articletime dependent EM-fields in cavity
Hi! First of I apologize in advance for any stupid questions but I'm a new COMSOL user and would like to model the field inside a resonator. This is no problem in the frequency domain but when I try to...
View ArticleHow to add a static current in Electromagnetic wave transient study
Hi, I am working on a problem using electromagnetic waves transient module. I want to study the interaction between incident EM waves and an annulus conductor in which a static current is flowing on...
View Articleinduced charge density
Hello everyone, I am working with the RF module of the Comsol 4.3b version. I am trying to calculated the dipole moments (px, py, pz) of a split ring resonator (SRR) illuminated by a plane wave. For...
View ArticleConvergence: when should I stop the model?
Hi everyone I have been working on models that take several days to solve. One of them is running at the moment, and I just have a general question. When I look at the Convergence Plot 2, which is...
View ArticleQuestion about modeling propagating plane wave (wave optics)
Hi, I am new to Comsol, so unfortunately I have little experience. I am trying to set up a very simple model in which I have a propagating plane wave in air, normally incident upon different materials...
View Articleserval questions of heat transfer in my project
Hello As the figure shows, I am using the fllowing models (Heat Transfer>Conjugate Heat Transfer>Laminar Flow Stationary situation Surface-to-Surface Radiation), and try to find the temperature...
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