3D Poisson equation problem coupled with Nernst-Planck equation
I used coupled Electrostatics physics and Transport of Diluted Species physics to simulate this problem. The source term in Poisson equation is the difference between cations and anions. Usually, the...
View ArticleSubsonic Ramjet Model
I am attempting to optimize the design of a ramjet to be created for rocket experimentation. I have been working on the model for the fall semester attempting to refine it. I am now using a 2d axis...
View ArticleLow Reynolds Turbulent Flow
Hi folks, does anyone know what the "spf.wall_spf" variable means in the AKN Low Reynolds k-ep model. I can see it in the equation view, but other than that, there is no more info... I am really trying...
View Articlebubbly flow: udrift in laminar flow...
Hi, I am currently working with the bubbly flow application mode in a laminar flow. The gaz velocity, ug, is computed thanks: ug=ug+uslip+udrift In the help, is it said that the drift velocity is...
View ArticleAssigning Materials
While assigning materials to some solids in my model, I am getting a red cross below the material name in Model Builder. What does that mean? What changes should I do to use those materials for the...
View ArticleSimulationtime for mapped meshes in 2D and 3D
Hi, Normally I used triangular meshes to simulate thin films on cantilever beams. Because of the very high aspect ratios I 've tried to use a mapped mesh for the rectangular geometry. The amount of...
View ArticleManipulating data from tables
Hi all, I'm working on a model using piezodevice physics in the frequency domain, and I'm trying to plot admittance in dB (rather than siemen). I've found the admittance by taking the surface integral...
View ArticleALE question
Hi, I'm interested in the transient effects of a moving charged object on a grounded one (see image). I have first modelled this using a parametric sweep on the object's x position. But of course, this...
View ArticleStraw Poll: Who would like to see the model gallery documentation overhauled???
Hello all, I thought I'd post this here to get the community opinions before suggesting it to support. If I want to learn how to use an aspect of Comsol I work through example models and I visit the...
View ArticleUsing step function in kinetic reaction simulation
Hi I am trying to simulate the kinetic reaction of biomolecule interaction in fludic channel expecting to have association and dissociation phase (concentration of complex versus time) in the same...
View ArticleSave the Date - COMSOL Conference 2013 Boston, Oct 9-11
Hello, We are excited to announce that the COMSOL Conference 2013 Boston will be held on October 9-11th. With over 50 events to choose from, including training and presentations, this is the premier...
View Articlejust start with a known solution for first time step
Hi, there is a simple solution, or? I perform a time-dependent study. But the input variable for the time is not long enough, so I want to repeat this pattern several times. Unfortunately it does not...
View ArticleEmbedding a Circle on the Curved Face of a Cylinder.
Hello, I am a new user. I am trying to create a model where there is a flux coming into the curved side of a Cylinder. The flux enters from a circular area connected to the curved edge of the cylinder,...
View ArticleError-Automatic remeshing
Hi, I encountered a problem about "Automatic remeshing" with "deformed geomerty" and Time-Dependent Solver When I ran the program, Comsol always displayed a Error: Unsupported operation on this type of...
View ArticleElectrostatics and Electric Circuit
I am relatively new to COMSOL. I am trying to simulate a two part problem. 1. An electric pole is placed underwater 2. A circuit is built around it to measure the voltage drop across a resistor The...
View ArticleDG method with periodic boundary conditions.
I am solving the incompressible Euler equations in 2d in vorticity-streamfunction formulation. The vorticity equation is w_t + grad.(Uw)=0 where U is the velocity and w is the vorticity. To solve the...
View Articlemaximum (or minimum) value in a time domain
Hi, I have a problem I cannot solve and you might help me. In my time-dependent analysis I would like to know the maximum of value of a variable, which has been reached at previous time steps. But I...
View ArticleHow to export data in excel format?
Hey Ivar, I want to export my figure into excel format. and replot it in matlab. Is it possible ? Thank you very much!! Baofeng
View Articleelectromagntic propagation through three layers
hello I am student on electronic and I am trying to simulate with comsol on rf module , in summarize my work is to simulate the sun light propagation through three layers bonded to each other and I had...
View ArticleStructural Mechanics Equation System
I am trying to understand how my structural mechanics model is computing its solution. The model solves and gives me a reasonable solution. However, I don't understand how it is arriving at its answer....
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