general pde mode, spherical coordinates
Hi, everybody I want to solve a differential equation in spherical coordinates (just “R” component dependent) By “General PDE mode” (comsol3.4). But there is no default spherical coordinates in the...
View ArticleVariables & Functions in Comsol 4.1
Hi, I am trying to do something very simple that worked perfectly in 3.5a, but that I cannot reproduce in 4.1. I have the feeling that I am totally missing something, but I do not know what. I define a...
View Articlecomsol software
Hai sir, i'm studying final yr electronics and instrumentation dept... i do my project based on 6 axis torque force sensor using comsol software.. so please give your opinion and suggestions....
View ArticleHeat Transfer in Soils
Hi, I am a comsol user and I want to have a 2d axisymmetric model. In my model, I have a soil sample that I put a steel bar in the soil. I want to heat the steel bar with a constant temperature 500(k)...
View ArticlePressure boundary conditions
Hi All, I am working on a coupled problem involving a piezoelectric and fluid.....I need to apply the pressure from the piezoelectric after each iteration step and apply it as a pressure boundary...
View ArticleProblems with sweep mesh
Hi, I have been trying to sweep mesh a domain (3-D). It will be like a small straight tube of rectangular cross section and having turns at right angles (like a serpentine). I tried to mesh the source...
View ArticleSloshing Tank with FSI
Hello All I calculate the waves of a water tank and then damp with a structure the waves. At the beginning I start with a single excitation an then wait and just let the gravity do the job. My model is...
View ArticleIll Conditioned Preconditioner
Hi everyone, I haver been trying to untangle this ill conditioned error with different meshings, which I think is the cause of the error. The temperature distribution in the soil (from 3D plot group -...
View ArticleE or E1 or E2 in my plasma model
Hello, I am trying since some days now to "copy" the microwave heated 2D model to a different geometry. My geometry is axial-symmetric in real. But I first started it in 2D only, but since I am not...
View ArticleHow to define Function in Definitions / Variables.
I'm currently working on electrical simulation using AC/DC module. I define nonlinear electric conductivity for zinc oxide material using following function(ZnO) in subdomain settings, but it shown...
View Articledomain deformation while doing moving mesh
Right now i am solving a moving mesh problem where the particle is moving in the domain. i have used moving wall and prescribed mesh velocity for the problem. It is doing fine for sometimes , however...
View ArticlePeak-to-peak amplitude in Comsol 4.3a ?
Hi I need to evaluate the peak-to-peak (pk-pk) amplitude of a voltage, which means the difference between the maximum positive and the maximum negative of a waveform. Are there any predefined function...
View ArticleHow to set displacement from study 1 as prescribed displacement in study 2?
Hey, I have a trouble with defining a prescribed displacement. Let's say that i received displacement of the edge caused by heating of sample. But displacement of this edge is different in every point...
View ArticleThere's pressure gradient, but no velocity, anyone can help me out? thanks
Hi, I'm using the Free and Porous Media Flow module to simulate the fluid flow on the particle level. I used it for 2D condition and it worked. When I switched to 3D case, something weird happened. I...
View Articlehow to make sure the soil is saturated
I am using poroelasticity module, how to make sure the porous media is saturated? is there any configuration to attain the totally saturated condition for porous media? thanks
View ArticleSpatially graded index / graded material properties
Hi, can anyone of you tell me if it is possible to define a graded index in comsol? It seems as if sth. like this has been done in www.comsol.se/academic/papers/2871/ But how? Is it simply possible to...
View ArticleGeometric nonlinearity
Hi, I have used structural mechanics to simulate an indenting sphere on a half space polymer film. I am changing the elastic modulus of the polymer film to go from hard material to soft material. I am...
View ArticleModeling Jet flow of Water in Air Atmosphere
Dear All I am modeling the flow of jet (say water or similar liquid) in an atmosphere of air. The problem is very similar to the one in the model library (the inkjet example). However, my domain...
View ArticleMovement of air due to thermal expansion
Hi everybody! I'm trying to simulate the movement of the air in 2D and I only get errors. I use two physics: laminar flow with heat transfer. I've created a square full of air and I put easy boundary...
View ArticlePostprocessing in cyclindrical coordinates
I am doing a plane strain analysis of a pipe with a crack in it. I would like to get the stress components in the cyclindridcal coordinate system (radial, hoop stress) rather than in the cartesian...
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