re : difference between eigen frequency, damped frequency and resonant...
I am a beginner in using COMSOL for the MEMS based cantilever design. please tell me the difference between the damped, eigen and resonant frequency. if all are different please help out with relation...
View Articlemicrophone simulation
Hello,I am bigginer in comsol and I want to simulate a dual perforated backplate microphone I recently started using COMSOL and I am totally on my own and would be really grateful if you could help me...
View ArticleAcoustic Levitation Simulation
Hi There is a tutorial model of "Acoustic Levitation" on the website, simulating the levitation using particle tracing for fluid flow. I want to simulate the levitation of a sphere (of diameter close...
View ArticleExport water table time series data from periodic Richards equation solution
Hi, is there an (easy) way to export a time series of the water table elevation (p=0 contour) from a time-dependent (periodic) Richards equation model? I have a 2D vertical rectangular grid with a...
View ArticleAssigning material permittivity which is a function of frequency and have to...
Hi I am struggling with a problem. I have a .dat file which contains three column.col 1 is for frequency col 2 is for epsilon_single prime and col 3 is for epsilon_double prime.... 1)how can i assign...
View ArticleInterface between a shell and a 3D domain element
I'm curious if anyone has any experience with the preferred way to couple the physical mechanical stress and strains between a 3D domain and a shell. This MEMs problem consists of a very thin Si3N4...
View Articleepoxy silica nano-composite material simulation
I am doing a project on simulation of electrical properties of epoxy-silica nano-composite material. The electrical properties include resistivity, loss tangent, relative permittivity, voltage and...
View ArticleBug in matlab livelink, 2D cut line 'genpoints'
Hi just want to give a heads up to anyone experiencing problems with retrieving data from a 2D cut-line in matlab. My objective: To get average air gap magnetic field over one pole span, by using 2D...
View ArticleSynchronous machine (torque)
Hi, I am new to COMSOL. I am tryng to build three phase synchrnous machine model. I have applied three phase voltage to the machine but unable to generate torque in a machine, I do not waht is wrong...
View ArticleDiffusion problem with sharp edge
Dear all, Using the 2D general PDE form within COMSOL, I'm trying to solve four coupled differenial equations, in order to obtain the velocity profile of an magnetohydrodynamic flow. One PDE for the...
View Articletorque and identity pair
Hi! I'm working on a 3-phase synchronous motor with interior permanent magnets. I have to perform both stationary and time dependent simulations. I split the air gap into two parts connected by an...
View Articlehow to know the effective mode index corresponds to the value of maximum.
When I use the RF module by the Mode Analysis, in which desired number of modes is 200, it is too much. However, I want to compute the maximum value of total electric energy for the entire effective...
View ArticleHow can I simulate microwave 2.45GHz interference in nanoparticles?
I'm using COMSOL to calculate the scattering parameters for a structure of nanoparticles for a microwave with a frequency of 2.45GHz. An error appears in the end of the calculation every time the size...
View ArticlePerforation Fins
Dear I'm a new user for COMSOL 4.2, so I need help in my project. How can I create a circular perforation in direction of flow through a pin fin as shown in attachment file. please, help me
View Articlek-e turbulence equation in coefficient form PDE
Hi, I am working on gas solid fluidized bed in Euler-Euler model laminar flow Module. The run is fine. Now I want to add k-e turbulence equations in Coefficient form PDE and solve the problem with...
View Article24 slot stator of synchronous machine!
Hi, If we have 24 slot stator, how can we apply three phase excitation to stator. I know how to deal with 6 slot stator but 24 slots are creating confusion. Any help will be highly appreciated. Thanks!...
View ArticlePiezoelectric axis definition
Hi All, I have some questions regarding the piezoelectric physics in the COMSOL. I'm using COMSOL multiphysics 4.3 Correct me if I'm wrong, in 3D model, the axes are 1 (x) (horizontal axis), 2 (y) (out...
View Articlewhy does "Undefined value found in the stiffness matrix" means?
I'm trying to simulate Photonic crystal. As far as I know, there is no need for me to know the stiffness of material in the crystal. However, when I click "compute", comsol always screen error message...
View ArticleWhich surface the terminal voltage should apply to in the electrostatics...
I want to calculate the electric capacity between two metal plates then I do a model in comsol as follow: I draw two blocks with a 2µm gap between them,and the material of the two blocks are set to...
View Articlecoupling a 1D geometry with a 2D geometry.
Hi, I wanted to know if it is possible to couple a 1D geometry to a 2D geometry the way I want to. In fact I am trying to solve a 2D model, but at every point in this model I need to get the solution...
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