Help: Why is Initial value changed after calculation?
Hello, everyone. I build two models （both are PDEs）in one file. For the first one, initial value is A0, a log-normal distribution. For the second one, initial value is B0, also a log-normal...
View Articleproblem with selecting the domain, boundary or edge
Hi All, I don't know if you guys have encountered such problem: when I try to select the domain, boundary or edge from the graphic window, I cannot select anything. It seems that the selection by...
View Articlecreating plots is extremely slow
Dear Forum, creating simple line plots (with global scope) of model results is extremely slow. For quite large model files (2-3 GB of size) it sometimes takes several hours for one simple plot on a...
View Articlesoil plasticity in poroelasticity
I am doing a project using poroelasticity interface, but I wan to consider plasticity behavior of porous materials, so I need to use plasticity constitutive model for porous materials. How do I add...
View Articlejava.lang.ClassCastException when using LiveLink from MATLAB
Hi there, I've been successfully using COMSOL and LiveLink for a few months now for generating and simulating electromagnetic models. However, yesterday I ran the same MATLAB code as I always do, but...
View ArticleMaximum number of Newton iterations reached
I have imported a 3D meshed model from simpleware to COMSOL 4.3b. Some of the materials of the model are Hyperelastic, Neo-Hookean. While running the model via Direct Solver at 99% of progress there is...
View ArticleOil Tank wtih heater
Hello, I am a new Comsol user. I am trying to model an oil tank heated by a U heater.The heater use oil at a higher temperature. The cold oil in the tank is at 30°C and the hot is at 250°C.I use...
View ArticleSelecting a point
I want to get the co-ordinates of an arbitrary region within my model so I can see how the pressure changes at that point. Does anybody know how to do this?
View ArticleHow to use Two Different Times steps in Solver Parameters?
Dear Sir, I am using COMSOL 3.5a. And I am running my simulation for 6hrs. But I want to run my simulation in two different time parts. (i.e. for 1hr i used solver parameters for time stepping range is...
View ArticlePhase change: freezing and convergence problem
Hi, I'm currently working on a water solution freezing model including the phase change. I use the COMSOL model : www.comsol.com/model/phase-change-474 Geometry: I just add a metal part below the...
View ArticleSetting a point to 1 and calculating impressed current density
Hello, I want to set a point to 1 in my geometry, and calculate the impressed current density that it creates. Gizem
View ArticleParametric Sweep of the Move funcion
Hi, I would like to so a simple parametric sweep of the position of an element in a 2D model. I define a parameter under global definitions and then under Geometry1 I Move1 by that parameter....
View ArticleFSI tutorial: Warning: Inverted mesh element near coordinates
I downloaded the FSI example from website. Fluid-Structure Interaction Model ID: 361www.comsol.com/model/fluid-structure-interaction-361 It is a classic problem. It looked good. But when I only changed...
View ArticleRelease Features
I'm running a simulation in the Free and Porous Media Flow physics and have run several successfully so far, but I've modified my geometry and am now receiving this error: Errors during multiphysics....
View Articleequation system
I want to use the following bidomain equation in my simulation :∇·((σi +σe)∇φe)=−∇·(σi∇Vm) I have two spheres one within the other as geometry. Inside the smaller sphere I want to introduce Vm as a...
View ArticleDifference between form union and form assembly
I performed the "compose" operation on my geometry deleting some parts which I did not want, but then when "from union" those deleted parts showed up again in the final geometry. Only when I do "form...
View Articleplacing electric and magnetic dipoles on top of thin (~50 nm) gold film
Hi, Can someone help me to model electric and magnetic dipoles on top of gold (~ 50 nm) thin film. I am using RF module for this. I'll really appreciate any help. Thanks.
View ArticleModel coupling to 2D to 3D geomety (General Extrusion)
hello all, I want to do a model coupling of 2D geometry and 3D. For this i used general extrusion coupling for that. I want to couple outlet ( along y axis) and inlet boundaries of 3D geometry through...
View Articleselecting the surfaces for surface-to-surface radiation
Hi, When I definie the surface-to-surface radiation boundary conditon, it is quite troublesome to select the surface one by one. Is there any easy way to select all surfaces for surface-to-surface...
View ArticleInfinite Elements - Electrostatics
Hi all, I try to simulate an charged object inside an unbounded region. I use the AC/DC module --> Electrostatics in Version 4.1. I attached the file. The outer bounds are ground and the charged...
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