Constant voltage at top surface of piezo
Hi, I want to apply compressive load on a piezo sensor (10mmx10mmx0.3mm) and ensure that its top surface should have constant voltage all along its area. How to ensure this constant voltage condition?...
View ArticleDielectric Loss in piezo sensors
HI, I want to give dielectric loss of 0.02 on a piezo sensor. I have tried by altering the 'dielectric loss setting' in 'model builder/piezoelectric devices/piezoelectric materials/damping and loss'...
View ArticleThick Cylinder under pressure
Plz tell me how can i model a thick cylinder under pressure as attached in the file. I made a 2D model, defined material, chose "solid mechanics". Applied a "boundary load" at inner circle boundaryand...
View ArticleReacting Flow in Porous Media
I am working on simulating a flow through a channel which is adjacent to a porous media which functions as an electrode to oxidize the electroactive species in the electrolyte (think fuel cell or flow...
View ArticleSimulating a rheometer
Hi Everyone, I'm a bit new to Comsol so sorry if this is a dumb question. I'm trying to simulate a rheometer in my lab. It's basically a cone in a petri dish. For simplicity I'm using 2-D and have...
View ArticleAccess depenant variable in Matlab code
Hi I am trying to develop a diffusion-reaction model using COMSOL - MATLAB interface. My model requires access to dependent variables during the execution so that they can be passed to an external...
View ArticleModeling magnetic nano-particles in a fluid
Hi all, We wants to model magnetic nano-particles in a fluid (fluid velocity is 0). We don't know which model to choose in the model navigator, and how to create a nano-particles. Thanks
View ArticleFailed to find consistent initial values.
Hi. I coose frekvenci transient study and get thise error. Failed to find consistent initial values. Last time step is not converged. THANK
View ArticleAcoustic velocity
Hello all, I am looking for a definition of acoustic velocity implemented in Comsol (Pressure acoustic/frequency domain - no flow). I want to make sure that what I am getting is exactly what I need....
View ArticleConvergence issues with level-set conservative form
Hello Everyone, I am trying level-set conservative form for droplet generation in flow focusing device. I have tried the following: (a) non-conservative form: it converges well but mass conservation is...
View ArticleCurrent density and resistance in piezoelectric device
I am trying to simulate the current density in a piezoelectric device. The geometry is a simple rod with a fixed boundary (also ground boundary) and a surface load on the opposite boundary. I can...
View Articlerf mems switch design (comsol 4.2a)
HeLLO, i'm working on designing a switch that should work on rf range. I'm able to draw 2d structure in work plane but still not able to fix one side of the cantilver beam. i hve following questions,...
View ArticlePML Coordinate Stretching
When I see the equation mode, PML in one of the direction (mapped coordinate e.g. y direction) is stretched to complex number but another remains only real for my 2D analysis, why is that? Also does...
View ArticleModelling Surface Plasmon Resonance on Nanorods
Hi. I am trying to model single gold nanorods of different size and shape extruding out of a thin gold layer with visible wavelength light incident upon it. The aim of this is to see how the geometry...
View ArticleSurface Density Charge As Function of Space
Hi, I have the following problem on Comsol 4.2. In my model I want to vary the Surface Charge Density depending on the radial direction r. When I enter it as a function exp(-r) in the "Surface Charge...
View ArticleAnalytic function in Geometry
Hello to everybody. Just a simple question, is there a way in Comsol to create a geometry using an analytic function? It seems to me it's not possible without going throught matlab and importing an...
View ArticleWind turbine tower
Hello everyone, I would like to design a wind turbine tower, along with the blades, in COMSOL 4.3. The parameters are: Height = 87.6m Base dia = 6m Base Steel thickness = 0.035m Top dia =3.87m Top...
View ArticleHow to obtain the density distribution
I’m working with soil plasticity and I want to obtain the density after the compression. Opening the model results the following error message: cannot evaluate expression. I don’t know what I have to...
View ArticleDifference between terminal Boundary condition and Electric potential...
Hi, I am modelling a free PZT patch. I have to apply a voltage potential of 20V across the top and bottom of the PZT patch. (attaching the model) I am doing it via two methods, (a) applying "electric...
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