Problem with Neumann boundary condition definition
Hi, I am simulating a Helmholtz equation (using the PDE mode module) with a Neumann boundary condition. Some days ago, we decided to update our Comsol version from 3.4 to 4.0. In the new version we...
View ArticleWhat's the difference between Form a union and Form an assembly?
comsol version 4 In Geometry, there is an interface called Finalize (Form Union or Form Assembly). What's the meanings of Form a union and Form an assembly? Is it like this? For example, when I creat...
View ArticleWhich interface choose for fluid flow with heat transfer
Good day! I would like to ask for an advice. I wish to solve the following problem: I have a plate of a solid material with low thermal conductivity. There is a pipe with cold water inside the plate....
View ArticleStore part of solution for next run
Hi: I have 2D and 3D models of the same experiment which are in the same file. I would like to do two things: 1) Store the solution of the 3D run and store seperately the data from a "cutplane". 2) Use...
View ArticleHow to specify the phase shift in electric currents (ec)
Hi, I try to reproduce the 3-phase cable simulation as shown in www.youtube.com/watch?v=ZCLcbSQB1-Q I used the electric currents physics and time-dependent. How to specify the phase shift among the...
View ArticleFinal Abstract Submission Deadline for COMSOL Conference 2013 Rotterdam –...
Dear COMSOL Users, The Final Abstract Submission deadline for the COMSOL Conference 2013 Rotterdam is Friday, August 23rd! Show the modeling and simulation community what you are working on, and get...
View ArticleCan cut line result be used in simulation?
I am currently using comsol to simulate a concentration lets name it C on a 2D symmetry rectangle. at one point I need to take a boundary value of C, I am wondering if there is anyway I can take the...
View ArticleSaving a file for later assemby
Hi, I want to model geometry of a complicated tool for later studies on Multibody dynamics module. As an start, I have created each part in different files and I have saved them as the mph file....
View ArticleDisplacement between two points
Hi I am very new to COMSOL and I am having trouble with calculating the displacement between two points. I'm using the structural mechanics module and I'm applying a body load to a an object and I want...
View ArticleApplying weak constraints in Darcy's law
Hi, I'm working on vapor intrusion modeling from subsurface into the overlying building. I have a large domain (100m X 100m) and a building (10m X 10m) with 2m basement is locating at center of the...
View ArticleScattering off a gold tip
Hey everyone, I'm having trouble with my model and was hoping someone could help me out. I am trying to model what happens when a frequency of light washes over a small tip of gold. My model is very...
View Articleinduced current in a loop, but with symmetry plane
I'm studying the induced current in a loop of wire from AC current driven in a nearby wire. The symmetry of the fields should allow for cutting the model in half, but I'm not sure of the BC's to use on...
View ArticleDisproportionate Number of Degrees of Freedom
Hi All Using an adapted mesh roughly numbering 2 million mesh elements, the solver calculates based on 14 million degrees of freedom which is outside my RAM capabilities (48Gb). When using a normal...
View Articlehow to limit the temperature below the melting point and also how to deal...
Hello I am dealing with a coupled problem of magnetic field and solid mechanic including plasticity deformation. As the copper is heated, the initial yield stress is reduced and also temperature...
View ArticleNanoparticle Growth
I have started working on nanoparticle growth kinetics and nucleation of the metal atoms. This is my first experience with COMSOL. I want to know how to start things off. Even a simple model is fine. I...
View ArticleHow to input AC E-field to the system?
I'm a beginniner in COMSOL. I think my questions is a little bit silly to ask, but I don't know how to proceed without help from your guys. I want to establish simply a system of two plate electrodes...
View Articlemicro-ring laser simulation COMSOL 4.3a
Dear everybody, If I want to simulate a micro-ring as a laser and a bus waveguide near it as the output coulper, which model should I use? Which solver? And how to set the input and output ports? How...
View Articleslip boundary condition
hello everyone i want to use slip boundary condition in channel flow with the upper plate moves. how can i write it with lattice boltzmann method? thank you
View ArticleLaboratory Plate Shaker
Hi everyone Im new to comsol, I have had some experience with Microfludics module. But now I need to simulate the velocity profile in a laboratory plate shaker (used for denaturing protein-protein...
View ArticleSpecifying a rotating boundary condition
I would like to simulate a rotating wall condition. For simplicity, imagine a square box. On the top surface of that box there is a circle. Inside of the box is a viscous fluid. I would like to impose...
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