How to define Neumann boundary condition?
Hi, Any body help me regarding Neumann boundary condition shown in this paper. I suppose this problem has been solved in comsol 3.5 by seelecke and presented in boston - 2008 conference. But i am...
View Articlenon uniform heat flux
Hello all, I'm trying to model simple 2D conduction model in a slab. What I want to do is use a non-uniform heat flux for a boundary condition. I already have the heat transfer coefficient distribution...
View ArticleProblems with S-parameter calculation
I do not understand the behavior of the transmission parameter S21 in a rectangular wave guide excited with two Port, there are differences in behavior between S21 and dBS21, these are the following...
View ArticleInverse heat transfer problem
Hello, I need to determine the surface temperature by doing an inverse heat transfer problem method. Experiments are done with impingement of a hot steel plate(900°C) with 3 thermocouples located at...
View ArticleOne boundary with two boundary conditions (Neumann and Dirichlet)
Please help me to understand about this issue. I have a system of two PDE equations with two variables (u1, u2) need to be solved in General Form. On a boundary 1, for example, I set up a Neumann...
View Articlestreamline problem
Hey, i am having some problems creating the steamlines for my Helmholtz coil. I followed the steps for the one of the model on comsol website for Helmholtz coil except other than revolve to create the...
View ArticleHow to Improve Convergence in Natural Convection
I am wondering how I can improve convergence in my natural convection model. It is a simple model; an isothermal aluminum plate in water. The model starts out fine but as the run continues (transient...
View ArticleSimulatneous temperature distribution...!
Dear Comsol Users, I am willing to come over to you again, this time with some questions I would like to be enlighted. I've built a 3D heat exchanger (coil) inside a material (cylinder) and with...
View ArticleVibrating horizontal plate.
Good Evening everyone, I have a really simple question, I'm sure someone knows the answer to my problem. I'm trying to make a model of a plate, platform, anything you want to call it, that vibrates...
View Article4 Point Bending of a Multi-Layer Bar with simultaneous phase transformations
Hello all, I have been trying to simulate a 4-point bending test of a multi-layer bar with a geometrically simple 2-d model on COMSOL 4.3a. For the better understanding of the case, The bar consists of...
View ArticleCompressible and transient flow problem
Hi, I am trying to model a tank full of air that empties with time through a thin channel (It is almost a nozzle). I used the laminar-transient formulation. I chose from the library the properties of...
View Articlemodeling heat transfer/heat loss of solenoid
heyo! working on a magnetic bearing project, and would like to find change in temperature a chosen distance outside solenoid due to current flow. also would like to find magnetic field and energy lost...
View ArticleA question about magnetic fields + solid mechanics
Dear all I am solving a simple problem with consol4.3a it is so simple. A solenoid with current I want to solve a stress by magnetic field. Until magnetic analysis is everything is okay but after I add...
View ArticleFailed to generate mesh
Hi all, I am trying to simulate the magnetic field of a permanent magnet. Initially the simulation worked. Later I changed the length of the magnet but an error arose saying A problem arose when...
View Articleproblem of self-defined parameter and build-in variables
I am using poroelasticity module. I have a problem about the self-defined parameter and build in variables. I defined shear modules,G, as a function of axial displacement, w (a build in variable), and...
View ArticleRunning the simulation for the required time span in more than one times (loops)
Dear sir, My requirement is "Running the simulation for the required time span in more than one times (loops)". I actually do not know the initial values of temperatures of the room that I am going to...
View Articlemagnetic forces direction in post-processing
Hi all, I have made a 2D simulation for the stress distribution due to magnetic forces in a synchronous reluctant machine, I want to show how the forces act on the boundaries of the stator teeth and...
View Articletriple point heat transfer gas, liquid, solid
Hello, I want to know if it possible (or if it exists some tips) for modeling a triple point where gas, solid and liquid are in contact each over. At this point I have a huge loss of heat by conduction...
View ArticleProblem in thermal stress modelling
Sir, I am working on thermal stress modelling on EDM process using COMSOL 4.0a. I am using heat flux as a input. At some places I am getting negative Surface Temperature which gives me wrong results of...
View ArticleMPCs in Comsol
Hi, I am a quite new user in Comsol and I have a doubt about the Multi-Point Constraint elements. I would like to know whether Comsol has anything similar to the MPC elements (RBE3 or RBE2) of Patran....
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