Result of the solution not equivalent to the initial boundary setting
Dear Sir Nagi Elabbasi, A pleasant day to you Sir. I would like to consult this problem that I'm having at the moment thinking that you can help me with this matter. Presently, I am doing a 3D...
View ArticleError in Two Phase Flow
I am using the Level Set Method in Comsol. When I am using the Time dependent solvers I get the following error- Failed to find consistent initial values. Last time step is not converged. The same...
View ArticleModeling packed bed reactor
Hi I am a beginner of COMSOL. I would like to design packed-bed reactor. The reactor diameter is 1 mm, and the particle size is about 1 micro meter. The porosity of packed bed is about 60%. If I want...
View Articlebuilding a multicomponent gas mixture in comsol
Hello All, I was wondering if someone could help me with building a multi-component gas mixture in COMSOL 4.2. I have my biogas composition of 66% CH4, 33% CO2 and 2% H2S and I need to define...
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 ArticleError - 3D LID Driven Cavity Flow
Hello Forum, i try a computation for the "3D lid-driven cavity flow" model. I got a Comsol Error: Failed to find a solution. Divergence of the linear iterations. Returned solution is not converged. I...
View ArticleHow to solve the problem of negative concentration
I am a totally new user on comsol. Now I try to simulate the mixing in the microchannel without reactions. I use the laminar flow and Transport of dilluted species. There is a similar example from...
View Articlecone-jet mode in electrostatic field
Hi, Here is my problem. I want to simulate a electrohydrodynamic (EHD) phenomenone , a nozzle with full water (or electrolyte) in a electrostatic field, the the water is polarized and deformed the...
View ArticleInconsistent uni-directional constraint with Conjugate Heat transfer
I am trying to model a simple high temperature hydrogen heat exchanger with the conjugate heat transfer module. While I have been sucessfull in modeling individual tubes of the hydrogen alone, I cannot...
View Article2way FSI simulation - deformation of pipe due to sinusoidal flow ...
Hello, I'm going to model a simple artery , here is the model definition: =========== Model data =========== A cylindrical artery with 10mm radius, 1mm thickness and 80mm length is considered with...
View ArticleCUDA and COMSOL
Dear all, I have a new NVIDIA Quadro GPU and I would like to use it to accelerate my simulations, is it possible to use it somehow? I looked for some informations and it seems to me that CUDA it's...
View Articleosmotic pressure
Hi all, we're two Politecnico di Milano's students using Comsol software (4.2a version) for our master thesis. On the Comsol webpage we've found an article of S. A. Conrad "Finite Element Analysis of...
View ArticleA 'net' like material - allows water to go trough but not particles?
Is there a possibility to define such a material? I want to do particle tracing a in fluid, but some of my walls require to allow water to go trough but to not particles ( or according to size..)
View ArticleSolution for Time-dependent Solver - not working properly
Hi All, I seem to be having a difficult time solving a time dependent solution for any of my darcy flow porous media models. The problem I am encountering is that all the time solutions that are stored...
View ArticleForces in particle trace
In the tutorial for doing particle trace in fluid flow, we are instructed to add the drag force. Is it possible to add additional forces such as Pressure gradient and acceleration forces? Many thanks,
View ArticleModelling blood flow in COMSOL on a rotating microfluidic platform
Hello everyone, I am trying to model blood flow in a rotating microfluidic platform. I came across this paper where they discuss the use of COMSOL Multiphysics in modelling blood flow ....
View Articledefine velocity boundary condition at membrane surface
Hi, I need to define velocity boundary condition at the surface of membrane that is permeable. do you have any suggestion? Thank you.
View ArticleHow to calculate the normal heat flux on a boundary
Hi everyone. I´m a beginner with COMSOL and I don’t understand how it calculates the normal heat flux on a boundary. In order to evaluate how to derive values in the Results section, I have followed...
View ArticleWater flow in a PVC pipe to measure impact of water pressure on it
Hello, I'm the beginner of Comsol Multiphysics. I wants to pass water though a PVC pipe. I have used a straight pipe using Turbulent Flow, k-ε. In geometry there are two domain one for water, another...
View ArticleConvergence problems
Hi there, Could any one give a hand? I have no idea what is happening with the solver or the model. I am trying to model a laminar flow without any other physics. The default plots during solving...
View Article