modelling end inductance and end resistance of an induction motor
Hi, I am trying to model end winding resistance and end inductance of an Induction motor using electric circuit interface. My model works fine and produces good results when I keep only resistance with...
View ArticleCombustion
Can anyone help? Calculate the equilibrium composition for the reaction H2O to H2 + ½ O2 for the ratios on n(H)/n(O) = 1.5. The temperature is 2500K, and the pressure is 3 atm. I have done it for...
View Articleweird air flow
Hi folks, I want to simulate an air flow. The real model is as follows: The air is sucked in by a fan and flows through 2 lattices which lie one on top of each other and have a distance of 4 mm. The...
View Articleheat conduction in solid
Hi, i try to simulate a 2D heat conduction in solid with comsol, i use an dimonsionless heat equation i have a square geometry with these bouadary conditions (0,0,0,1), when i draw the isothermal...
View ArticleCoupling between PDE and Electrostatics
Dear All, Does any one have any experience of solving a steady general form of PDE with steady electrostaics module. I am trying to solve a PDE [ Div(DuE) = 0] where D is the mobility coefficient and E...
View ArticleQuality factor in 3D
Hi All, I am working on a 3D geometry and trying to obtain eigenfrequencies and quality factor in RF module. But it seems, eventhough Comsol can find the eigenfrequencies correctly, quality factor...
View ArticleModeling of busbars
Greetings to the whole community, I am currently working on the simulation of a busbar (made of three parallel drives). But I can not get good results (my expected results are different from those...
View ArticleColor Legend
Hello I have a question about color legends for 3D plots. I have two system that I want to compare and each of them simulated separately. Now that i want to compare them i found out that they have...
View ArticleError in multiphysics compilation/Problem setting up multigrid
Hi, I got error message from Comsol v5.2. I attached. I am working with electric currents, heat transfer and semiconductor modules. Can anyone help me? Any ideas? Thanks,
View ArticleSolving coupled PDE's in COMSOL 5.2
Hi! Is there any way to solve coupled PDE's without using the Coefficient form PDE? I am not able to fit in my equations using that module. Also, How can i custom add boundary conditions(I am not able...
View Articlesingularity. error
Hello, Does anyboday know why I encounter the below error message in Comsol 3.5a? Error: Time 7.86913096623935e-007: Repeated error test failures. May have reached a Last time step is not converged....
View Articleoptimization solver;topology
Hello,When iam using the optimization solver to solve a topology optimization problem of eigenfrequency with MMA argorithm,i find i can not chose a study step of eigenfrequency ?and this question is...
View ArticleErrors in Electromechanical copuling with Nernst-Planck equation
I tried to simulate the electromechanics of polymer-metal actuator (IPMC) with involve ions migration i.e. Nernst-Planck equation. I made 2 components i.e. Studies (time dependent) with identity...
View ArticleWhy the same program sometime need 4000 secs and sometimes 300 secs
May I ask if anyone know why the same comsol program sometime need 4000 secs and sometimes 300 secs to solve? Exactly the same one, I didn't change any parameters, mesh, solver, just run it
View Article2D Axisymmetric Schottky diode
Hi, I am working on 2D axisymmetric Schottky simulation using COMSOL 5.1, but I have a problem with the results, after changing the doping concentration from n-type (donor doping concentration) to...
View ArticleModelling Room Air Environment in COMSOL
Hi Everyone, I need to define a Room Air Environment in COMSOL, in which I need to measure a Air Pressure at a specific point on the object plane. I am not sure how can I define the Physics for Air...
View ArticleMultiphysics simulation error
Hello, I would like to have one of the help on my work that I am currently doing with my version 5.1. I made all the necessary adjustments for my simulation but it does not end because of an error...
View ArticleConvection in a hollow cylinder between solid domains
Hey everyone, I'm trying to simulate the heat distribution of three electrical power cables with a constant load current buried in soil with COMSOL Multiphysics 5.1. The geometry consists of a...
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 Article"Include Geometric Nonlinearity" for Membrane
Greetings, I read through the manual for Membrane node and found that "Include Geometric Nonlinearity" is necessary to be checked in the Study Step. This is to include the prestress specified in...
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