absorbing boundary condition for heat transfer problem
Hi, can I give a absorbing boundary condition for a transient heat transfer problem. This is to avoid the heat wave reflecting at the boundary and contributing to the temperature rise. Can someone help?
View ArticleEuler-Euler Model: reached singularity
I am running a Euler-Euler model and get a singularity error about six seconds into a 12 second analysis. It appears that there is a high velocity flair at an inlet when the singularity occurs. I have...
View Articleharmonic perturbation
I have a question about harmonic perturbation I assigned a 1 A current to a cylinder in mf physics using multi-turn coil and solved it with a 60Hz frequency using frequency domain. If I assign 0.1 A to...
View ArticlePML Scaling factor in COMSOL 4.3
Hi, I am doing a 3D simulation with COMSOL 4.3 to find the field distribution and the mode of a waveguide where all the cladding, the core and the substrate have different refractive index. I have...
View ArticleCOMSOL Failing at Simple DE?
I've encountered a very simple problem with COMSOL's eigenvalue solver and I was wondering if anyone else has had the same problem. I'm trying to solve the simplest DE imaginable. I'm trying to find...
View ArticleConfine Modes
HI, I am doing a structure eigen-mode analysis. How can I only see the longitudinal mode and filter out other modes? Thank you
View ArticleWhat does it mean to have imaginary part for the force (AC/DC module)?
Hi, I am running a simulation to calculate the force between two conductors carrying AC current. I used MF with simple two circles of copper and surrounding of air. I set current density 200 in z...
View ArticleApplying time derivative as a dirchlet boundary condition
Hi, I need to apply the time derivative of a displacement created in a piezomaterial as the velocity for a fluid boundary..... Could someone please let me know as to how this can be handled in...
View Articlebatch file
Hey. How to use batch files. And where is possible to find documentation on this topic. Thank you.
View ArticleHow to save a solution
Hello , I have a question about how to save a Comsol solution. I did a model in Comsol 4.2 , after 31hs I got a solution , I saved the model but when I opened it again the solution was not there , so I...
View ArticleHeat Transfer in a bitumen tanker
I am trying to model a steel tanker filled with molten bitumen. The tanker is insulated and the bitumen is heated by two propane burners ( in form of U) located at the bottom. For the bitumen I have...
View ArticleInitially Stressed Bimorph Beam - Electrostatic Actuation
Dear All, I am attempting to model a bimorph which naturally deflects upwards due to stress in the lower layer of the beam. So far, this part has been successful. The top of the bimorph is silicon, and...
View ArticleSolving Time dependent problem with stationary solver at the same time.
Hi, I am trying to simulate a brushless DC motor. I want to make comsol to solve the problem in the form of time dependent. However, during each time step, comsol should solve and obtain a stationary...
View ArticleCalling all electrochemical enthusiasts - March courses on Electrodeposition...
Join us this March for our special courses focused solely on electrochemical applications. First, we will be offering our popular Electrodeposition course where we will cover electrode kinetics, the...
View Articlethe electric potential dependent on temperature
hello, please help me i am trying to make a model of an electrode in a cylinder of biological tissue, i want to make the electric potential on the electrode dependent on the temperature of the tissue,...
View ArticlePlacing a finite element model into an electrical circuit in COMSOL 4.1
Hello, I have recently made the switch from COMSOL 3.5a to COMSOL 4.1, and I am currently unable to do things that I used to be able to do very easily, namely placing my 3-D model (drawn and defined in...
View ArticleTutorial: Working between COMSOL 4.1 and MATLAB 2010b
Ok, here is what I figured out in order to be able to take a COMSOL model, modify it in MATLAB and then reopen it in COMSOL for further work: 1. Launch COMSOL normally; 2. Launch MATLAB by using...
View ArticleDefining MIXTURE of gases
hi friends i want to define a mixture of gases (iodine,xe,radon) at inlet each with different concentration for diffusion in the air . how can define mixture with different conc in comsol .
View ArticleMovement of air due to thermal expansion
Hi everybody! I'm trying to simulate the movement of the air in 2D and I only get errors. I use two physics: laminar flow with heat transfer. I've created a square full of air and I put easy boundary...
View ArticleImported SolidWorks part doesn't behave correctly
I'm relatively new to COMSOL but I haven't had much luck finding a solution. I had an assembly in SolidWorks made of 3 parts. I created a new SolidWorks part file which had the 3 parts mated together...
View Article