Comsol elementary question
Hi everyone, I have been comsoling for an year but i didn't get this doubt till now. I am modeling one ode which looks something like this u``=function(u(x+1),u(x),u(x-1)), where u`` is derivative of u...
View Article1D Schrodinger equation
Dear Comsol users, I want to solve radial Schrodinger equation for Hydrogen atom in comsol. So I use 1D axisymmetric coefficient form PDE and solve for eigenvalues with boundary conditions as u =0for...
View ArticlePlot the interpolation graph in 3.5a
Hi, I am using COMSOL 3.5a and solving heat transfer (solid-liquid interface) problem for 1hr. Generally, to plot the graph,I used file-export-current plot and values are open and finally I plot the...
View Articlemie scattering off gold nanoparticle in water
Hi. I have been calculating the absorption and scattering cross section from a gold nanoparticle in air correctly using the example in the model exchange:www.comsol.com/community/exchange/215/ However...
View ArticleEvaluate Torque applied on a disc
Hello, I'm a new user of Comsol. I am trying to do a simple test of applying a torque to a disc and then simply evaluating it. I believe I have managed to apply a torque correctly to my disc, but I...
View Articlepostprocessing of results
Hello, I have a working3D Model in Comsol4.3b. This model gives me the 3D electrig field of an electrode array. To evaluate this model I want to do some postprocessing im Matlab. Especially an FFT over...
View Articleacoustic pressure, frequency response on modal basis
Hi all, I am using Comsol 4.3a and I can't find what's wrong with my use of the frequency response study using reduced model. This is my second post on the subject, as the first one didn't attract much...
View ArticleProblems with a PDE Coefficient Form model
Dear All, I am trying to solve an electrical potential distribution problem studied on a 1D axial symmetric model using the PDE Coefficient Form module. My model is comprised of five coupled problems:...
View ArticleTreatment of sharp corners when using acoustic module
Hello, I have a quick question which puzzled me a bit. For some time I was using Comsol's acoustic module to perform frequency analysis of the internal cavities. I always assumed that sharp edges in my...
View Articleglobal equations (ODE) and global variables
Hi, I'm trying to define an equation in global equations and it is corresponded with the coordinates x and y (or certain global variable), e.g.: States Name (u) Equation f(u,ut,utt,t) Init (u) u u-rho...
View ArticleUnexpected error occured whenever I click on a field for text input in tables
I've recently installed a copy of COMSOL 4.2 on Mac OS 10.8.5. The program runs fine except that an error message would pop up whenever I need to edit a text field in a table, such as parameters and...
View ArticleThe transfer function of a impulse response
Hi all: My problem as bellows: 1.A cantilever plate: the length 300mm, the width 200mm, the thickness 6mm; the clamped end dimension : the length 60mm, the width 50mm, the thickness 6mm.(see Fig 1) 2....
View ArticleCoupling Thermoelectromechanical problems
Hi All I want to coupled three things, thermal +structural + electrical problems and solve them all together not separately. Any idea how to do it in COMSOL. I ave attached the coupled equations. Thanks,
View ArticleAC/DC module,Simulating a parallel capacitor(Two Circular discs)
Hi, I'm using AC/DC module ---->Electrostatics----------->Stationary study in Comsol. I have tried simulating parallel plate circular electrodes having diameter 63 mm.I'm trying to see how...
View ArticleComb Drive
Hello Everyone!! I am trying to simulate a 3d Comb drive structure which will have some displacement when voltage applied to the combs, however its giving errors as I cant apply "Fixed Constraint" to...
View ArticleSandwich panel - Solid & shell intercation
I am a new COMSOL user. I am trying to model a sandwich panel maiden of a wood core and carbon fiber skin. My idea is to model the core with solid and the skin as shell. I have already read some topics...
View ArticleHow to control the model step by step in particle tracking?
Hi, everyone. I'm currently working on an particle tracing problem in which the particle density is changing with time. Therefore, I need to calculate the particel density every time step (or every...
View ArticleDifference between contact pair and identity boundary pair
Hi, I am new to Comsol and I was building my model, a cylinder inserted into a closed end sleeve. Load is applied on the top surface of the inner cylinder (like a piston-cylinder configuration). They...
View ArticleCalculating % volume of 3D domain encompassed by a surface
I am running version 4.0a. I have a system with transient diffusion of dilute species (implemented via the 'transport in dilute species' physics) throughout a cylindrical domain. To visualise my...
View ArticleHow to put the friction in the comsol???
Hello! I wonder something.......... i should put some data in the boundary settings of equation system. But that result was so weird.... i think the results in slip and frition states is not same. but...
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