Please help! (error: Undefined value found)
Hello everyone, I’m working on the following model from Comsol library: Batteries and fuel cells>>ht_pem. When I change the geometry to a more complex one, for example using two or three...
View ArticleEigen-frequency analysis of metal grating
Dear all, For a metal grating (see attached Structure_Reference.jpg), now I would like to analysis the dispersion relationship of surface plasmon wave supported by a metal grating, which propagates...
View ArticleMie Scattering problem, Csmcol 4.2a
Dear Fellows, I want to find module about "Mie Scattering", but I can not access to this module.www.comsol.com/showroom/gallery/3459/ Is that module still exist in the gallery or not? Thank you for...
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 Articlecannot select an edge to become an outlet boundary
Hi! After struggling for quite a while with 4.2a, I haven't been able to enable one edge to become an outlet. What I did was to construct two objects: the first one is a sequence of lines, which I then...
View ArticleDefining wires in 3d models
I am trying to simulate a process that includes flow, electrostatics and mass conservation. The model is simply a rectangular. One edge is grounded and the opposite includes 59 wires. The grounded edge...
View Articlevolume within a closed isosurface
Hello WIthin a 3D domain containing closed isosurfaces, is there a way to calculate the volume of material contained within each isosurface? Many thanks Dan
View ArticleTime dependant signal at inlet
Hi all! I am trying to implement a time-dependant inlet velocity. What does 'location' mean and what unit is associated with this variable? Is it time or length? If length, is it meter of millimeter?...
View ArticleProjection of an Isosurface onto a plane or boundary
Hello Another visualization question: Is it possible to plot the projection of an Isosurface in 3D space onto a 2D surface or plane (such as the x-y plane). Thanks in advance Dan
View ArticleExtract voltage with lumped port?
Total COMSOL newbie here, please be gentle :-) After some struggle and a lot of looking at the model library, I managed to set up a simple 2D model of a plane wave incident on a pair of metal strips...
View Articlestudy
sir, I got different voltage for the same frequency value when i compute in frequency domain and in eigen frequency which value is correct
View ArticleHeat continuity
Good afternoon! I need an advice about how to use the heat continuity option please. The task is to describe the following situation: in my model, there are some details that are physically not in...
View ArticleComputing physic in dependence of another physic
Does anybody know, if there's a model in the model gallery, where you compute a pyhsic in dependence of another physic?
View ArticleModal damping ratio
Hello all, Anyone knows how can I calculate modal damping ratio for a rotor if I have access to eigenvalue? Thank you, Br, Hessam
View ArticleElectric Field Simulation Problem
Hi, I am trying to create a plot of electric field, but i failed to do it. I created a simple model of column, and I used the physics of "Magnetic and Electric Fields". I defined a electrical potential...
View ArticleNeed help: Error whenever trying to simulate periodic boundary condition in...
Hi Everybody, I'm trying to do 3D RF module simulation with periodic boundary condition on the sides. Every time i start the computation, i keep getting an error that says : Unknown function or...
View ArticleCOMSOL Releases COMSOL Multiphysics version 4.3a
We at COMSOL are proud to introduce version 4.3a of COMSOL Multiphysics to the COMSOL community See: www.comsol.com/products/4.3a/ This introduces: * LiveLink™ for Excel® * LiveLink™ for Solid Edge® *...
View ArticleTemperature mapping with Model Coupling
I wish to generate temperatures in a model and subsequently map the temperatures them to a similar model in a different study. The two models will have the same geometry. However, the model will be...
View ArticleSimulation of the magnetic fied
Hi, I have one physical NdFeB magnet and I need to simulate this magnet in Comsol 4.2a, but I dont know exactly how to do it. I know these parameters of the magnet: Remanence Br = 1380 mT Coercivity...
View ArticleEvaluate the electrical voltage from the magnetic field (mf) physic
Hi ! I need to calculate the electrical voltage of an electric conductor subdued to a magnetic field. The conductor is excited by a current density using magnetic field physic (mf). I want to simulate...
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