How to write stop condition in solver
I am using a COMSOL V 3.5. I would like to use stop condition for time or temperature in solver parameters. Can you suggest me the how to write a equation for particular time or temperature? Thanks in...
View ArticleAcoustic transmission through periodic structures
In the underwater acoustic structure interaction problem I have done a @D problem in 3.5a version. When I convert this to 3D in 4.3b what is the periodic boundary condition to be given. In 3.5a version...
View ArticleAcoustic properties of a ventilation duct
I am trying to model a ventilation duct to try and and understand what happens to sound within a duct and when it exits the duct into a room. I am trying to look at the sound pressure variation and...
View Articleboundary condition dependent on dependent variable
Hello everybody, In a coupled heat and mass transfer problem, I would like a pressure BC to get updated at each time step. Let's call this pressure pv. pv depends on the temperature and pressure...
View ArticleConstant 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 ArticleHow to calculate the reflectance and transmittance using scattering wave...
Dear communities: Recently I am trying to model my 3D periodic structure with COMSOL 4.3b. The periodicity of my sturctuture is 1.5um, but the incident wavelength can be as low as 400nm, so that the...
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 Article