Calculating the Electric Field by applying a potential
Hello Everybody, I want to simulate the following problem: I have a geometry (for simplicity assume it is e.g. a box) which is hollow (there is a vacuum inside), and the boundaries consist of some...
View ArticleJoule Heating - Resistive Heaters
Hi, I've built a COMSOL model that models the joule heating of electrodes that are designed to heat up channels in a microfluidic device. I am able to choose a V0 (input voltage) run a transient study...
View ArticleGeneral question about multiple steps in solid mechanics
Hello everyone, I have what may turn out to be a question which makes me look like a dummy! I have been looking in the documentation for information regarding multiple steps in a simulation. For...
View ArticleTrouble coupling heat transfer physics for both fluids and solids
Hey all, So I'm getting stuck with my model where I try to couple three different physics. The three physics are: Electric Currents, Heat transfer in Solids, and Heat transfer in Fluids. Basically what...
View ArticleLater version of COMSOL has robuster and stabler solvers
Dear all, I just want to share my recent experience with a convergence problem. During last several weeks I was struggling with convergence problem. The model has two 2nd-order PDE and Electromagnetic...
View Articlesegregated vs fully coupled solver in comsol
Hi All, I have compared these two solvers for a heat transfer case with surface-to-surface radiation. Acutually simulation results, i.e., temperature distribution in the domain, are quite different....
View Articleout of memory during assembly
Hi All, I am running a heat transfer with radiation, and the error message says "out of memory during assembly". Rigth now, I am using a workstation with 48GB memory. I check the element number, and it...
View ArticleAcoustic Band Structure of Metamaterials
Hi folks, I have been trying to find the band structure of an acoustic metamaterial. I have been attempting to adapt the "Bandgap analysis of Photonic Crystal" tutorial given for COMSOL 3.5a to 4.3. I...
View ArticleStructural optimisation
Hi, I am using a livelink from Solidworks to Comsol in order to import 3D geometry and quickly define some geometry parameters. I've made a structural analysis with applying torque load to my model and...
View Articleinternal DOF
Hi All, I am running a case with element number of 0.18M, and number of degrees of freedom solved is 311413 (plus 200428 internal DOFs). What is the internal DOF? And I select the fully coupled solver....
View Articleradiation heat transfer
Hi Ivar, Since you are the expert in radiation heat transfer, I wonder if you can help with some problem in radiation heat transfer. I am running a 3D case with surface-to-surface radiation heat...
View Articlefrequency domain using reduced basis (modal)
Hi all, I'm trying to make a frequency sweep on a (big) model of an acoustic cavity, with specified surface impedance as boundary conditions. If I use the "Frequency domain" study, everything goes...
View ArticleCUDA and COMSOL
Dear all, I have a new NVIDIA Quadro GPU and I would like to use it to accelerate my simulations, is it possible to use it somehow? I looked for some informations and it seems to me that CUDA it's...
View ArticleCoefficient form PDE with Dirichlet boundary conditions - Problem with...
Hello, I have a Coefficient form PDE with Dirichlet boundary conditions with two dependent variables. The dependent variables range -5<v1<5 for v1 and 250<v2<600 for v2. The model converges...
View Articlehow to simulate the strain/stress of the beam at 1m/s2 70Hz acceleroration?
Dear Sir, I have read several of your very useful answers here. Thanks a lot. I built a beam structure using the solid mechanics model, did the stationary strain/stress analysis without any problem. I...
View ArticleRadio frequency (and general) convergence question
I have a model which COMSOL is having a very difficult time finding a stationary solution for - the solver gets a fair way, but then tends to oscillate and never settles down to a converged solution....
View ArticleMulti-steps simulation (100 and more)
Hi! Is there any way to optimize solver to solve hundreds of steps? I'm trying to simulate tunnel construction process and there is a lot of steps. Right now with standard settings at the beginning...
View ArticleAcoustic-Structure Model
Good evening, I am attempting to model the response of a fixed beam when driven by an acoustic source within a fluid. Initially, I used an eigenfrequency study and obtained results that make sense to...
View ArticleFailed to Evaluate Jacobian Variable
Dear COMSOL users, I am trying to model the electromagnetic heating stimulation for heavy oil reservoir (2D radial) to be further studied for my bachelor's degree thesis. The model is very simple. I am...
View ArticleFluid across cylinder with heat source
Hi! I am doing a small project about an heat exchanger. First I should study the Reynolds number effect and the vortex shedding. I already have some results about that (I should be able to calculate...
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