Axisymmetric Hertzian Contact mechanics model
Hi, I am trying to model a sphere pushing on a surface. To do so, I have created a 2D axisymmetric model with a point load close to the apex of the half-circle; as putting a point load right at the...
View ArticleHow to Couple Free and Porous Media Flow with Heat Transfer In Solids
Hi Everyone, I am new to COMSOL and I am trying to simulate a solar panel cooling system. I am trying to simulate in 2D the heat transfer between a thin rectangular layer (the photovoltaic cell),...
View ArticlePDE
I am currently working on COMSOL 4.0a. Can anybody tell me how the variables for stress are defined in COMSOL? Since I want to define a Coefficient PDE, which its diffusion coefficient (c) is coupled...
View ArticleMWP combined with DC
Dear Daniel, I am geting tired of comsoling... because I do not know anymore what I can do to make my models converge. i started with the waveguide microwave plasma from the model-library. I put some...
View Articlehorizontal stress only shows in the top layer
hi i'm simulating a road using the elastic model. the road has 3 layers (asphalt, foundation, soil) with different moduli. when I apply the loads of the wheels, I can clearly see how the vertical...
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 ArticleModel 4.3 vs 4.3b not converging
Hi folks! I've just updated from 4.3 to 4.3b and I'm trying to get some convergence but to no avail. I'm using the Mixture Model with the Schiller-Naumann slip model for settling suspensions. I get...
View ArticleViscoplasticity: stationary and transient modeling
Hi! I am trying to work on a model that has both viscoplasticity (Anand model from the Nonlinear Structural Materials Module) and contact. First, it seems like I'm having penetration. A stationary...
View ArticleAccessing prior solutions while solving a Time-Dependent Study
I am trying to create a condition for my bioheat transfer simulations that will deactivate blood perfusion effects when the maximum temperature (at any previous time point) exceeds 60 degrees Celsius....
View ArticleWill the increase of the relative tolerance reduce the solving time ?
Dear all, as mentioned in the title, I would know if the change (specifically an increase) of the relative tolerance in Time Dependent solver (but also in Stationary solver, why not) will reduce the...
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 ArticleConvergence problem with Comsol 4.3b
Hi Everyone When I run the model in the 4.3a, it can work very well. The convergence firstly is about 1e4 to 1e5. When the comsol software is updated from 4.3a to 4.3b, the convergence becomes 8e8 and...
View Articlehow to show the error curve
Hi All, Normally there is an error curve to show the convegence speed when running a case. However, I closed some windon in Graphic and this error curve is not shown. Wihout this curve, I am not able...
View ArticleTime integration of a variable over the domain
Hi, I am solving a periodic fluid flow problem over a 2D domain. I need to find the time averaging of the term u*ux+u*vy at each point on the domain. I tried defining a global ODE but it gave an error...
View Articlesegregated vs fully coupled solver in comsol
Hi All, I have compared these two solvers for a heat transfer case with surface-to-surface radiation. Acutually simulation results, i.e., temperature distribution in the domain, are quite different....
View ArticleLinear elastic material
Hi, I implied two linear solid mechanic (linear elastic material) in two rectangular(( Rectangular1)and rectangular2 ) ), there is a common inner boundary( number 2) between these two rectangular, i...
View Articleperistaltic pump model convergence
Hello, I am working on a model that is similar to the peristaltic pump model available in the “model gallery”. I would like to use this example to present my problem. The peristaltic pump model does...
View Articlesolver sequences
Hi, I am simulating fluid flow and heat transfer in a cylindrical pipe. what i need is a very long term simulation (i.e., 25 years) and I am using pipe flow module which assumes the pipe and 1D and the...
View ArticleProblem 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 ArticleTransport of diluted species and electrostatics
Dear Community, I am trying to combine the physics of the poisson equation (electrostatics) with the nernst-planck (transport of diluted species) in Comsol 4.1 for like 6 weeks now, and all I get is...
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