Absorbing boundary for acoustics
Dear all. I am trying to simulate a acoustics wave propagating through the air. The absorbing boundary that I set is "Matched Boundary". Is this a correct setting? The result went weird when the...
View ArticlePlot
Hi everybody I simulate the rib waveguide with mode analysis and in picture i attack it ,is a 3D plot. I want to convert it to 1D plot in x and y direction.How can i do it?I think it is so easy but i...
View ArticleInstallation error
Hi, I am trying to install 4.3b version. After installation and starting up the program I get the following error: License error -15.
View Articlethe best way to implement the anisotropic PML
For my master degree thesis, I’m doing some simulations on photonic bandgap fibers and I would ask you information on the PML. In particular, I'd like to know which is the best way to implement the...
View ArticleHelp for a better 3D mesh
Hello! I am a beginner in COMSOL and i need some help with a 3 D mesh! In my model i have to focus on the cylinders and around them. So i need finer mesh for this area but coarser mesh for the rest in...
View Articleacoustic and structure deflection couple field
hi, I am interested in finding out the sound pressure generation when we release pressurized air on the diaphragm of pressure(air) horn, Till now i have modeled 3d model of air horn, plz suggest me...
View Articlecomsol 4.0 how to have unequal scaling on different axes
In comsol 3.5a, i could selected under options->axes/grid settings the option that the axes not be equal. I have problems where dimension along one of the axis are microns while along the other axes...
View ArticleLiveLink "selection.set"
Hello All, I'm having what I believe to be a pretty straightforward problem getting the selection.set function to work properly. I am learning LiveLink by building up a model step by step, exporting to...
View ArticleAC/DC model: Matrix has zero on diagonal.
Hi everybody. I have to calculate the magnetic field around three cables. The model I built simply includes the three straight conductors and air around them. A small voltage difference is applied and...
View ArticleAdapative Mesh Refinement with Mapped Distribution
Hello, I'm using Comsol version 4.3 and, for some reason, when I try to use adaptive mesh refinement in the Stationary Solver's extensions, it claims I can only use triangular mesh elements for it. I...
View Articlesilencer duct
Hi I want to simulate insertion loss for ventilation ducts. I need to define inlet and outlet pressure so i can calculate insertion loss by its difference. There is a similar sample "perforated...
View Articlecan i calculate the absorption coefficients of absorber composed of...
hi, i am a new to comsol,. And i want to calculate the absorption coefficients of a absorber composed of micro-perforated plate and porous material. can i calculate the coefficients of micro-perforated...
View ArticlePML Error: Could not find any cartesian regions
Hi I am new to PML. I am using Structural mechanics module to implement PML in a cantliver to determine the waves propagating to the PML. I am getting this error: Could not find any cartesian regions....
View ArticleAdding points and lines to 3D models with parametric surfaces
Hi all, I was wondering if there is a way to add a point or line to a model in which I have a 3D block with the top surface replaced by a parametric surface derived from a DEM (digital elevation...
View ArticleElectric potential and current density analysis
Dear friends, I analyzed a model using Time-dependent solver and for the time: range (0, 0.016,1). The model is consisted of different layers with different conductivity and permittivity and a Terminal...
View ArticleRotating machinery for gas liquid system in stirred vessel
Hi everyone, How can I combine multiphase system with rotating machinery system. As far as I know, the physics for rotating machinery only for single phase. But I need to run a simulation for a liquid...
View Articlehow to achieve this laser beam movement
Hi i am trying to move laser beam on surface of a square plate for layer scan. i tried from last 2 months. but i could not achieve this movement. i have attached the figure for laser beam movement....
View ArticleVariable axial and radial pith in helical structure
Hi How is it possible to define increasing axial and radial pith for helical structure(let say helix is along z direction, need to define pith as a function of z)?Can you please show me here with an...
View Articlelarge parameter sweep
I performed a parameter sweep for 5 separate parameters (3 separate values for each). So, the simulation ran 3^5=243 separate times. However, when I look under the accumulated probe table, the results...
View ArticleDrag Force
Hello, I'm new to COMSOL and I've been trying to estimate the drag force on a model I've built in Solidworks. I've looked around and it's been difficult to find information on how this can be done. The...
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