Problem: Cylinder appears to be block
I am quite new to this program and I tried to do create a 3D circular duct. I selected Cylinder and chose a radius of 0.004 m. In case of a short height compared to the radius, the cylinder keeps its...
View ArticleResonant condition
i am generating a resonator model in comcol 4.2. i am using solid mechanics module. In that module i am creating damping to make vibration. but i achieved only surface deformation my 1D plot showing 0...
View ArticleInvalid curve or surface
I keep getting this error when I try and mesh using a free tetrahedral mesh. any ideas?
View Article3D particle tracing only computes in 2D
I have a problem with my simulation in COMSOL 4.3b. I am working on a project where particles in a microchannel are driven my magnetic forces. I already successfully finished the model in 2D but in 3D...
View ArticleEquation editing in Structural physics in Comsol 4.0
Hi Everyone, I was exploring comsol 4.0. I found that the GUI is good but some functionalities in 3.5a are removed. I wanted to edit the Structural physics equation system to suit my PDE. In comsol...
View ArticleIntegration of a value over cross-section
Hello everyone, I have a model of molecular diffusion in a cylinder (axisymmetric geometry), and after solving (stationary solver) I get the concentration field c(r,z). I would like to get rid of the r...
View Articleconversion from 2D to 3D
hello, I am building a 'comb drive' model, in the 'electrostatics' division of the 'AC/DC module' in COMSOL 4.2. I need to 'extrude' a 2D model into a 3D one. How do i do that? Thank you
View ArticleEditing equationin at Expression in Variables from Equation views
Hi all, I’m playing with thermo-mechanic coupling. In the mechanical part, I use solid mechanics with Norton Creep. In this creep, I would like to have nD=1. That’s why I’ve changed Expression in...
View ArticleGeneric 3D color/contour plot of parametric sweep values
Hi, I do a parametric sweep and sweep two variables (say, width=1,2,3; height=4,5,6). I select the dropdown box that says "All combinations" so that I get all combinations - i.e. width=1 and height=4...
View ArticleEmpty parameter list
Hi everyone, I'm beginner to COMSOL and I'm modeling hyperthermia cancer treatment with magnetic nano particles. I'm using bioheat transfer for the body cells, mixture model for modeling nano particle...
View Articleelectrostatic potential induced by charges
Hi, I am fairly new to comsol, your help would be helpful, I have an electrostatic model composed of two electrodes and medium( air, plastic), just like an parallel capacitor. In my 2D model, I built a...
View Articlesine waveform
Hello Please help me, my model is a electrode in a cylinder of tissue. i want to put a AC voltage on the electrode. i defined sine waveform (wv1) from (global definitions> functions> waveform)...
View ArticleSurface reaction - diffusion: Robin condition
Hello, I am working on implementing a reaction-diffusion model. I have a particle in solution, where a reaction is occurring at the surface. I want to implement a Robin condition in the boundary of the...
View ArticleHow to add a padlock in wave equation,electric?
Hi Everyone, I was exploring comsol 4.2a. faced a problem in applying it. As can be seen from my attach file, there is a small difference between the two Wave Equations.There is a padlock in the second...
View ArticleFace mesh does not respect face vertices
So I am trying to create a boundary layer mesh for a fluid flow model. I keep getting the following error Face mesh does not respect face vertices. What does this mean?
View Articlefinding fringe capacitance
hello sir i am new in comsol. i am trying to find capacitance of a device ..when voltage of drain=voltage of source=0 volt and gate =6 volt. but i don't know how to put boundary conditions on the...
View Articleacoustics
Dear sir, i am using acoustics equations are writing in Matlab. i need some help from you. In same equation are introduce in comsol and also avilable for matlab programs are introduce in comsol. give...
View ArticleHeat exchange during ice cube formation !
Hi, I'm trying to solve a heat exchange problem coupled to a phase change in 2D. The model consists in a small volume of water on contact with a metal plate. I cool down the plate gradually so at some...
View ArticleImplementing non-standard boundary condition
I am trying to solve a standard diffusion pde in potential form. The resulting equation consists of a term with a first-order time deriviation and another term with a second-order space deriviation....
View Articleimpose heat flux fluid/fluid Interfaces: laminar (tpf) and heat transfer in...
All, I would like to impose a heat flux on a 2D fluid/fluid interface. I have considered utilizing an equivalent volumetric generation using the delta function and even the tpf.Vfi function to turn on...
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