Problem : Face is (or has a narrow region that is) much smaller than the...
Hi everyone! I'm trying to mesh a model using Free Thetrahedal with extra fine size. But I keep getting a message telling me that a single face is much smaller than the element size. I used to get an...
View ArticleConvert the version 3.5 mph file to version 4.2a
Hi, I am a user of 4.2a and my collaborator is using 3.5. I cannot use the file he sent to me. Would you please help to convert the attached mph file to 4.2a? Many thanks! Xiaoxiao
View Articlea question in the "electrochemical_polishing" example in comsol model library.
Dear Ivar Kjelberg, I am a comsol user, recently i am learning to use the "deformed geometry" function in comsol 4.2a, There is a good example in the model library named "electrochemical polishing". I...
View Articleparameters names must not be empty
Hey, again, this is an error I ha with comsol 4.3: parameters names must not be empty I need a quick help attached is my comsol file, you just need to run it and see the error. and also i attached a...
View Articlefunctions dependent on other functions
Hello all, I have 2 random functions in my model- rn1 and rn2. I need rn2 to be dependent on rn1, but when I try to call rn1 into the rn2 function, comsol does not recognize it as a variable. Does any...
View ArticleModeling a Diode
Hi, I am trying to follow the example of semiconductor diode available in: http://www.comsol.com/showroom/documentation/model/114/ in a COMSOL 4.2. I believe that I have followed exactly what is...
View ArticleA doubt in the piezoelectric module involving mechanical simulation
I observed some interesting empirical observations where the thickness mode vibration of a PZT strip helps trigger a coupling motion to unscrew a nut from a long screw. This long screw is attached to a...
View Articletwo-phase flow in porous media
Hi, I want to create a model for two-phase flow in porous media. I found an example in model gallery (Model ID:499) which is similar to my model (the example built in version 3.5a but my version is...
View ArticleApplying a +/- 10 V sinusoidal signal to electrodes in air
Hi there Been playing around with COMSOL in an effort to learn how to use it. I have some success modelling my little arrangement with the electrostatics module: a row of electrodes in the middle,...
View ArticleMie Scattering problem, Csmcol 4.2a
Dear Fellows, I want to find module about "Mie Scattering", but I can not access to this module. http://www.comsol.com/showroom/gallery/3459/ Is that module still exist in the gallery or not? Thank you...
View ArticleOptimization of the voltage according to an image
Dear all, this question is maybe easy for many of you. But this is very new to me. I need to optimize voltage on different places of piezoelectric actuator. I need it according to an image (of...
View ArticleRF, 3D rib waveguide propagation. The no solution / poor convergence issue.
Hi, I'm modeling a complex 3D rib waveguide structure. I'm following the examples and solving boundary modes for both ports (1 excited) in study 1, and then choosing the correct mode I want to...
View ArticleMultilayer thin film
Hi I want to create a multilayer thin film and want to put boundary (diffusion) condition at the interface between two layer. How could I proceed with that ? Any help would be appreciated
View ArticleMEMS
How can i compute the displacement due to gravity in a silicon proof mass in accelerometer and therefore i need to compute the change in capacitance in the accelerometer. My basic question is how do i...
View ArticleIteration in COMSOL
Hello, I have a problem here. I want to use COMSOL for one of my problems. In this model, I want to find the viscosity and velocity in a geometry which I have both soil and water. So I should use...
View ArticleUndefined value found
Hello, I ran across this problem in the computation, using Solid Mechanics and Fluid Flow. Undefined value found. - Detail: Undefined value found in the stiffness matrix. .There are 553 equations...
View Articlepore scale model:autocad import
I have created a model in autocad. I wish to simulate fluid flow in it(a porous media). it is a mdoel of grain particles. the problem is that at the import stage,i am getting error message that the...
View ArticleExport animation/image sequence via Matlab Livelink
Hi, I'm have a HT problem which I solve time dependently via the Matlab Livelink. Since I have a lot of models to solve this way, I would like to export the image sequence of the solution automatically...
View ArticleThermal losses from RF Electromagnetic Waves
Dear all, my problem is the coupling between an RF probelm and a thermal problem, do to the test I made 2 "attached" Blocks and I solve before an RF problem on block1 with the calculation of the...
View ArticleTrouble coupling heat transfer physics for both fluids and solids
Hey all, So I'm getting stuck with my model where I try to couple three different physics. The three physics are: Electric Currents, Heat transfer in Solids, and Heat transfer in Fluids. Basically what...
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