Global ODE or General form PDE
Hi everyone, i need to input this equation into my model and i am very unsure as to how you go about doing it. td * (du/dt) = T_avg > Td td = time taken T_avg = average temperature of the cell Td =...
View Articlework with deformed geometry
Dear Colleagues, I have to perform nonlinear analysis on thin walled columns. Before performing this study I need to model geometric imperfections. I want to follow this procedure: 1) perform a...
View ArticleSimulation error
Hi , I am getting this type of error whey i am trying to start simulation. "Variables property does not include all variables in Xmesh" Could anybody can give me any solution/ suggestion. Thank you...
View Articlemagnetic field gradient in 3D return zero!
Hi everybody If anybody knows that why the gradient of magnetic field in 3D models is always zero? I checked the different methods. for example I wrote d(Bx,x) or different component of B and H. Even...
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 ArticleCoupled PDEs, Last time step is not converged
Hi, I am new to COMSOL, and what I encountered is about coupled PDEs. I have two coupled PDEs in one physics model in general form. One is about heat transfer (T), the other is an ODE used for the...
View ArticleDEP particle tracing for fluid flow COMSOL 4.3 simulation
Hi, I've tried to simulate dielectrophoresis by using the particle tracing for fluid flow module of COMSOL 4.3, but I' ve encountered some problems with the dielectrophoresis force. I am trying to...
View ArticleError while simulating Trussed Leg
I am currently doing a simulation on both Cylindrical and Trussed Leg for Jackup Units. I have ended the simulations for Cylindrical Legs using Comsol 4.3b. Sadly, I am getting an error while using 4.4...
View ArticleAuxiliary problem on different domain
Good afternoon! I am simulating the reaction-diffusion problem in 2 domains separated by a membrane with transmission conditions on this membrane. I have 3 reaction-diffusion equations for 3 functions:...
View ArticleCOMSOL help needed. (RF module - Heating of water using waveguide)
Hello there, I am a relatively new COMSOL user who is in the process of validating a paper, to be able to get a better grasp at COMSOL. The paper I am trying to validate using my simulation can be...
View ArticleFailed to find consistent initial values
I am fairly new to COMSOL and I realize this topic has been covered in the discussion forum, and one of the major problems seem to be that the initial conditions are too far from the final solution....
View Articleabout MUMPS allocaion factor increased
When I use MUMPS solver, the warning is MUMPS allocaion factor increases to 1.44. What is the mean? Although the warning is exist, I can also get the result, then the result is right? What is the...
View ArticleStrange issue with laminar flow level set method
Hi, I recently started using the laminar flow level set method to simulate the motion of water in a partially filled channel as air flows above it. The simulation runs well when the distance scales are...
View ArticleHoping for a match.
Hello everyone, Before starting simulating tensile tests on defective steel bars, I want to make sure that the software behaves properly : I define the behavior of my material by interpolating some...
View Articleerror: may have reached singularity
Hi what is meant by this error"repeated error test failures, may have reached singularity" and at what place does the error come from? from mesh, geometry, or what? i try to model DC Discharge plasma...
View ArticleError in DEP simulation-Help
Hi All, I m getting simulation error while simulating DEP based separation.I choose particle tracing with time dependent study, I m able to simulate for laminar-starionary, electric field-stationary.....
View ArticleRandom relative error for identical compute run
I have just spent... don't ask.... a long time doing dozens of runs of the attached 2 plate capacitor driven in EC by a CIR current source single pulse. * CONVERGES fine. Identical every time. BUT I...
View Articleswitch off saving of recovery files in Matlab code
Hello community, I am running Comsol through the Matlab interface. My problem is that the directory assigned to the recovery files is to small to save them which terminates my calculations. I would...
View ArticleJava Runtime Environment error
Getting following error, A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0x0000003da3efbc6c, pid=6909, tid=46912497239488 # # JRE version: 6.0_20-b02 # Java VM:...
View Articlehow to use the "Previous solution" as initial value for new analysis
Any idea how to use the "Previous solution" as initial value for new analysis, for the sake of solution convergence?? Preferably, step-by-step procedure! Thanks, Hina
View Article