Transport of diluted species and electrostatics
Dear Community, I am trying to combine the physics of the poisson equation (electrostatics) with the nernst-planck (transport of diluted species) in Comsol 4.1 for like 6 weeks now, and all I get is...
View ArticleWeak form for 2-D elasticity
In an effort to learn COMSOL, I decided to model the two-dimensional elasticity equations using the weak form. I was surprised looking through the documentation that there are very few example...
View Articlescaling of variables
What is scaling of variables and how does this influence the final solution? What should be chosen for scaling of variables from "manual, initial value based, automatic, none"? Thanks for the help....
View Articlethe free vibration of the cantilever
Hi everyone: The initial displacement D=1.05mm, is placed on the end of the cantilever beam, to solve the velocity response of the beam end. First, I select space dimension 2D, and add physics Beam,...
View Articleinitial Values of Variables Solved For
Hi, I have someting to know. As you know, the initial condition set is as follows: initial Values of Variables Solved For Method: initial expression, Solution Solution: Zero, Solver1, Solver2 in...
View ArticleCan I pause the calculation and check the intermediate result?
Hi All, Can I pause the calculaiton of COMSOL and check the intermediate result? I would like to check if the intermediate result is reasonable or not. I don't want to only depend on the convergence...
View ArticleWeak Form PDE: how to impose Neumann BCs?
Hi everyone, I'm new in Comsol, so I apologise in advance if my question is trivial. I'm exploring Comsol capabilities in solving PDEs, and my current unidimensional equation is the follow: A(u) u'' =...
View ArticleJoining Edges (results)
Hello All, I have a situation where I have a parametric sweep, and I get a couple of solutions (all having the same geometry). I can use the join operator to subtract the solutions and I get something...
View ArticleHow can I manage individual cell values of a mesh in a convergence process?
Using module Semiconductors for computing Electric Potential for a certain geometry, sometimes during convergence process one can observe how few cells close to both exterior limits of a domain and...
View ArticleConvergence problems simulating a thin film - structural mechanics coupling
Hey everybody! My goal is to simulate the stresses during a load cycle in a bearing shell. The problem: I assembled a journal bearing in con-rod from which i cut off the major part so that the...
View ArticleHeat Transfer
Hello I'm a student on the project, and I'm messing in COMSOL 4.0 a short time and have no notion of "heat transfer", I need to get the temperature to stabilize so you can compare with the real model!...
View ArticleCyclic Voltammetry (CV)
1) I am using the electroanalysis physics module with the built-in CV study only. How does one define the two electrodes which the CV is being applied, in the case of a two-electrode setup? 2) Is there...
View ArticleConvergence problem in a simple geometry with Joule heating module
Hi guys, I am modeling a simple geometry (some stacked layers) with um and nm dimensions in comsol 4.3b. The convergence plot goes down rapidly at first and after some iterations it seems that the...
View ArticleMhd model of a crucible furnace
Dear collegues, i´m setting the procedure to evaluate the movement of the molten metal in a simple crucible furnace: reading the papers from comsol (...
View ArticleSuccessive simulation in COMSOL 4.3
Hello everybody! I am curently doing simulations of fluid flows in microfluidic channels. The total simulation domain is quite big and a mesh that could provide a solution with resonable precision...
View ArticleOptimization problem
Hi everybody! Please give a hand. Knowing the experimental value of the function (for example, the maximum temperature of the body at a specific point), I need to find the optimal value of parameter...
View ArticleFresnel Equations Model Frequency Sweep
Hey guys, I would like to change the COMSOL Wave Optics/RF model, the Fresnel Equations model, to change the transmission and reflectance vs. alpha to transmission and reflectance vs....
View Articlehow to optimize the result of comsol with matlab??
Hello everyone! I want to know how to optimize my problem. already i got the result from matlab using the m.file which is from Comsol. Afterthat, I don't know how to solve that... Because I didn't use...
View ArticleGeneric Error
Hello everyone, I am using the COMSOL 4.4 AC/DC Module to reach the saturation of an electrical steel block with the help of (two) current coils. Therefore I implemented a HB-curve in the materials...
View ArticleTime dependent solver of unsteady Navier Stokes
Hi, I'm simulating flow of incompressible fluid in periodic media. I have implemented dimensionless Navier Stokes equations with Comsol PDE module. 1- I resolve my problem with a steady solver (for...
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