Error: Undefined value found.
Hi, I am simulating a nano antenna in RF module and I get this error: Undefined value found. - Detail: NaN_or_Inf_found_when_solving_linear_system_using_SOR I also simulated the same model in 2D...
View ArticleHow to mesh this concrete slab with embedded loop
This is a concrete slab with embedded loop. I don't want to use the free tetrahedral to mesh this model since the result is not as accurate as quad element do if the order of the shape function is the...
View ArticleHelp for my case!
Hi, I am new to Comsol, and I want to simulate a water droplet falling down and pass through the 2mm gap between two circle particles. (see attached file) the important thing is that I have to consider...
View ArticleUndefined value found.
Hello, when I solution emw, it has a error : Undefined value found. - Detail: NaN_or_Inf_found_when_solving_linear_system_using_SOR what's this message meaning ? Thank you!
View ArticleApplying AC voltage
Hi all, I'm currently studying the electromechanical effects of a water droplet under AC/DC voltages. The water droplet is placed between two rectangular electrodes. I've applied a electric potential...
View ArticlePorous Monolith in a pipe
Dear All, i'm studying heat transfer in a pipe where there is a SiC monolith surrounded by an insulating mat (see screenshot). Up to now I have studied the system considering the monolith as pure solid...
View Articleelectric field and potential distribution
Hi I have been working on a 3D (AC/DC) model of a insulator, and I am trying to verify the uniform potential and field distribution along the insulator surface. I apply 33Kv voltage at HV end. I got...
View Articleresistivity plotting
Hi I am running a stationary model of a wire network usinf Electric currents and Heat transfer in solids . Each copper wire (linearised reistivity) has a constant current. There are heat losses to the...
View Articlecalling a waveform from Definition node
Dear all, I want to apply AC voltage to an electrode. I built my desired stimulation waveform from Definition node. How can I call this function? Do I have to enter function name in Electric Current...
View ArticleThermal expansion
Hello! I'm trying to simulate the thermal expansion of a solid silicon block, which is cooled down from 293.15K to 80K. Heatflux or something like that is not important, I'm just interested in the...
View ArticleLinearly Polarized (LP) modes
Hi all, I'm willing to calculate linearly polarized modes, that is, modes with only four non-zero components and azimuthal symmetry in a multimode optical fiber (see for example...
View ArticleHow can I define an PML in model solids mechanics ?
I need a help ! I'm using a model of a small rectangle onto a large rectangle 2D axisymmetric to denote of wave propagation I have to put the PML absorbed wave to not be reflects But when i put it and...
View ArticleMultiple user in Linux?
Hi, since some time I use Comsol on a Linux machine. Because of some former trouble I changed the directory used for temporary files to my home directory (followwing the advice given in solution number...
View ArticleUsing a 2D eigenvalue solution as a scattering boundary input in a 3D simulation
Dear all, I have a simulation that solves for a whispering gallery mode in a toroidal geometry. This is done using a 2D PDE solver. This file is attached and is adapted from Mark Oxborrow's work:...
View ArticleLaminar Flow +Chemical Reaction
Hi, Can anyone please help me with my model and guide me as to where I am going wrong. I am trying to simulate a simple chemical reaction A+B-->C in a pipe filled with water flowing at laminar...
View ArticleParametric Study making functions
Hi there, I am doing a parametric study with a variable T_initial for a frequency domain simulation for a fixed range of frequencies, this worked well I need now to change the set of frequencies with a...
View ArticleNew version
I have a model which I created in 4.3a and that ran OK in 4.3a. I have updated to 4.3b today, but the model won't run :( I get various errors including: Failed to evaluate operator Jacobian. Failed to...
View ArticleBrinkman Equation; Anisotropic Permeability
Can I specify an anisotropic permeability with COMSOL 4.3a; Subsurface Flow Module; Brinkman Equation? When I go to user defined, I can assign a single value only. I can't enter a tensor or specify...
View Articlecomsol 4.2a with matlab R2011a
Hi, I saved the comsol file in matlab as told. The tutorial says open ''COMSOL with MATLAB''. What does that mean? Also i get an error as follows when i run the m file of the comsol model. Undefined...
View ArticleUniform Magnetic field?
Hi everyone, I am wondering how I can generate a uniform magnetic field in Comsol. Basically, I want to simulate a metal particle moving in this uniform field. Now I am thinking put all the particles...
View Article