How 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 ArticleHow to use Laminar Flow Pressure results in Solid Mechanics, help?
Hi, I need to use as an input in the Solid Mecanic module the Pressure results from Laminar Flow calculations. Can anyone explain me how to do this? thank you for yor answer. Best regards, Leonardo.
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 Articlewhy it is different between Axial 2D and 3D in Non-Newtonian Flow.
Hellow, i have used this for about 2 weeks. but i have some problems. so i need some help. i drawn a model of the cylinder which is same both them. and they are same values, boudary conditions... but...
View ArticleThe affect of air flow on cantilever
I'm working on a project on COMSOL to study the affect of flow on cantilever, I used laminar flow and solid mechanics in my model. I drew the cantilever with fixed end in a box. two surfaces of the box...
View ArticleNo change in laminar flow simulation results even after changing material...
Hi, I have been doing very straight-forward and simple laminar flow simulations in a chamber. I have observed that flow simulation results don't change if I add and use another fluid with different...
View Articlemems based capacitive type humidity sensor
Hello I am working on capacitive type humidity sensor in which I've to model diffusion of humidity in polymide layer that will change the permittivity of polymide hence changing the capacitance between...
View ArticleInput for inlet of Charged Particle Tracing
Dear Comsol gurus, I'd like to know if there is a technique to read out a file with exact initial positions and velocities for the charged particle tracing. I don't mind using Matlab via the Livelink,...
View ArticleModeling a closed vessel pre-stressed by its internal fluid
Hi, I am trying to model the dynamic deformation of a vessel which contains incompressible fluid (fully encapsulated) under external load. At the initial state, the fluid has internal pressure such...
View ArticleProblem to converge a Reaction engineering, Diluted species transport and...
I want to degrade one component in a 3D geometry along with diluted species transport and laminar flow in it. My simulation runs okay in stationary study (i used step function here). But when i want to...
View Articlecan you explain how to put the friction??
Hello, I'd like to learn how the friction in 3D Non-Newtonian mode is given the comsol. please, let me know if you know that.
View ArticleHow to define a mixture of two miscible liquids at the inlet?
Hello, I have a question about how to define a mixture of two miscible liquids (for instance water and ethanol) at the inlet. My 2D geometry is as follows: I have two parallel rectangles (representing...
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 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 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.
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