Encountering error during meshing
when I try to run a mesh i encounter the following error message: "Edge is much shorter than the specified minimum element size." I do not know what this means and any advice on how to get rid of this...
View Article2D model coupling
I want to couple two 2D models, the first models computes a stationary state and the second should use the result to compute a time dependent model. I thought that with identity mapping I could read...
View ArticleParticle absorption and refraction
Hello. How to simulate refraction and absorption in Mathematical particle tracing module. Maybe I should add another physics. I could simulate reflection by choosing wall condition. Any suggestions?...
View ArticleMesh dependency !
Hello, I wanted to ask about meshing a 3D problem. I'm doing a validation for 3D channel with radiation between the inner side of the channel (surface to surface radiation). I'm facing a problem when I...
View Articlecalculate resistance of a numeric multi turn coil in freqency domane is to high
Dear all, I hope anybody in this Forum have the same exipiriance width the multi turn coil damane. In my model i have a simple numeric multy-turn-coil domane. My problem is that the calculate...
View ArticleTime dependent boundary
Hi all, I have flow through a cylinder, and want the inlet velocity to be periodic [ u(r,t) ]. Im new to comsol and havent been able to find an answer to this. Thanks in advance for any help!.
View Articleprecipitation around grains in porous medium
Hi, I am trying to build a model where the idea is that after a chemical reaction CaCl2 + Na2CO3 => CaCO3 (s) + 2 NaCl. CaCO3 precipitate and is immobile. I am using the Reaction Engineering (re),...
View ArticleImplementation of boundary conditons at liquid-liquid interface
Hi all, I am simulating a liquid-liquid flow in a channel. The liquid-liquid interface appears to be curved as one phase liquid is dispersed as droplets. I have used the laminar flow single phase...
View ArticleMass transport in tube.
Ok, so I solved the unsteady laminar fluid flow in the tube im looking at. Now, I want to add in a mass transport problem. Say I have a sphere of concentrated dye at the center of the tube, and want to...
View ArticleHydrodynamic drag
Hi All, I am trying to simulate the hydrodynamic drag force on a particle of 8um suspended in a fluid which is flowing at a flow rate of 20uL/min through the micro-channel of 15umx15um entrance/exit...
View ArticleProblems with parametric sweep
I have a model that I want to investigate with differens values on at least one of the design variables. If I change the variables value manually and compute, there is no problem but if i use variable...
View ArticleExporting Specific Mesh Data
I am quite new to Comsol so please excuse my ignorance when trying to explain my problem. I am currently working with a model of a redox flow battery, and I am interested in exporting data such as flow...
View ArticleTransmission Spectra in RF module
Hi, I'm a beginner in COMSOL. I am using the COMSOL scripting in MatLab. I would like to know how I can get the transmission spectra as shown in Fig 4 of the file attached below. I am looking to plot...
View ArticleTransient elastohydrodynamic squeeze film interaction
Hi COMSOL geniuses, I am trying to do exactly this with the Fluid Structure Interaction Module. www.comsol.com/showroom/documentation/model/14109/ I am running a 2D axis symmetric simulation and would...
View ArticleUsing integration coupling variables
Dear all and Ivar Kjelberg, I used to integration coupling variable--->Point variables in order to derive integration velocity (u) and I got displacement (dr) in results for the case of 2D. But...
View ArticleVery high displacements shown in resonating MEMS devices
Hi, I have been modelling several structures of MEMS resonators and when I do the eigenfrequency analysis, I am getting displacements of the order of 1 m while the size of the structures is of the...
View ArticleData export to text in 3.5a
Hello all, Could you kindly tell me how to - 1) export data from a Cross section plot to text file? 2) How to plot two sets of data along the same plot? Thanking in advance.
View Articlehow can i print pdf doc
Hello using my spare time to start learning 4.0, I ran into a basic and unexpected difficulty: I tried to print portion of the pdf doc for off screen reading.. [ I have the 3.5 book but 4.0, as an...
View ArticleParticle tracing - particle counting
Hello to everyone, Im new to COMSOL and currently trying to work with particle tracing for fluid flow. The model we are working on is part of vascular network and we are using as physics : structural...
View ArticleSlow matlab livelink with comsol 4.3a
Hi everyone I have a Comsol 4.3a model which takes about 4½ minutes to run. I would like to run it through MatLab to do sweeps over several parameters and only save a few results from each run. However...
View Article