Output pressure of the transducer adding Vac + Vdc
hello, I 'm working on a capacitive transducer, using the electromechanics(emi) model. Now I want to observe the output pressure of the transducer in the frequency domain and I add a voltage V=Vac+50...
View Articleerror in statonary analysis of a biased resonator
Dear comsol community, I'm working on comsol4.2a , I would be glad if i can get a solution for my following two queries: 1) I have gone through the modelling instructions given in the 'Stationary...
View ArticleResonance frequency of beam (calculation+plot)
HI I want to calculate and plot resonance frequency of cantilever that I designed in MEMS module. Based on the previous discussions here I understand that I should do the study in "Eigenfrequency" and...
View ArticleNeed Help with Simulating Thermal Stresses in a Layered Plate
Hi Experts, I kept running into this message: Failed to find a solution. System matrix is zero. Returned solution is not converged. I wasn't sure what exactly went wrong in my model. I'd really...
View ArticleAbsorbing boundary condition for transient wave propagation problem
Hi! I am wondering if I can define an absorbing boundary condition for a transient ultrasonic wave propagation problem (let's say in a 2D plane strain transient module). The option certainly doesn't...
View Article2D geometry but illuminated from below
Hi, I want to create a 2D geometry but illuminate it from below, or out of plane, with a plane wave. Whenever I try and set the Background Field as exp(-i*emw.k0*z) (in x direction) I get errors as it...
View ArticleComsoe error when useing with MATLAB
I have an error that continually comes up when useing MATLAB and trying to have the program access comsol. I get one of two errors the first is Feature Compile Equations: Time Dependant (so11/st1)...
View Article[SOLVED] Preferences are not saved in Comsol 4.3a on Windows
The problem story: 1. I went to Options > Preferences > Graphics > Rendering, set it to "Software", because it often crashes with OpenGL on my machine. 2. It says "The program needs to be...
View ArticleA confusing point between tutorial "Plasmonic_Wire_Grating" and...
Hi all, Recently I'm confused by the different periodic condition settings between tutorial "Plasmonic_Wire_Grating" and "Periodic_Boundary_Condition". In the "Plasmonic_Wire_Grating" periodic...
View Articleproblem of user defined function
I am using poroelasticity module. I defined a analytic function named G. It is a function of poro.eZ (strain component in z direction), G=f(poro.eZ), and I can plot out the figure of the G(poro.eZ)...
View ArticlePlacing a finite element model into an electrical circuit in COMSOL 4.1
Hello, I have recently made the switch from COMSOL 3.5a to COMSOL 4.1, and I am currently unable to do things that I used to be able to do very easily, namely placing my 3-D model (drawn and defined in...
View ArticlePostprocessing in cyclindrical coordinates
I am doing a plane strain analysis of a pipe with a crack in it. I would like to get the stress components in the cyclindridcal coordinate system (radial, hoop stress) rather than in the cartesian...
View ArticleI export only S11 as S Parameter what about s12,21,22 ?
Dear memebrs I used the Date Export and then emws11 and when I open my exported file I see only the S11 parameter what about the s12,s22 ?? how can I export them too. See a screen shot of my issue I...
View Articleparticle deformation througn a contrained channel
Hi there, I am doing COMSOL simulation to see the behavior of a particle flow through a microchannel. There is a area of the channel where particle size is greater than the cross section. So the...
View ArticleHow to restrict the scale of calculation
Well, I'm interested in a model as attached. I'm using the Structural Mechanics Module in order to calculate a deformation at low temperature caused by different thermal expansion coefficients....
View ArticleHow to make two different time ranges periodic in time dependent study
Dear all, I'm trying to simulate a multi-physics model and one of them is heat transfer. I'm giving a pulse heat source where I use periodic rectangle function. I define the pulse duration as "tt" and...
View ArticleInterfacial boundary conditions for structural mechanics module
Hi, Does any one knows how to impose a continuous displacement boundary condition on an interfacial boundary between two geometries in solid stress-strain module of Comsol 3.5(a). Kindest regards
View ArticlePost processing
Dear all, every time I edit one parameter of a graph, COMSOL redraw it automatically. Is possible to disable this feature? Thanks
View ArticlePDE and ODE implementation
Hello, I am trying to simulate frost growth on a surface but I face difficulties implementing the equations in PDE and ODE interfaces. Can I have some help ? I attached a .pdf with the equations. Best...
View ArticleSolver Robustness in Joule Heating Model with Field and Temperature Dependent...
Hi there, I am trying to solve a Joule heating problem in 2D axial symmetry. The challenge in this system is the temperature "T" and electric field "E" dependence of the conductivity "sigma" of one of...
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