How to set classpath from GUI
Hello, I have created a library of java code to make complex tasks, and I would like to use other libraries from within this code, which are only available in .jar format. When I run my .class file...
View ArticleParticle tracing: timing issues
Hello, I have created a simulation suite that calculates the electrostatic field of a given device and traces particles through this field. Since none of the available particle release nodes suited my...
View Articleask help for engenfrequency of the Helmholtz resonator
Hello，everyone I'm doing a kind of capacitive ultrasonic transducer and I want to combine the transducer with resonator to make the output acoustic pressure larger. There are lots of questions and I 'm...
View ArticleLaminar flow module in Comsol 4.3a
Hi, everyone, I am using laminar flow module in Comsol 4.3a to model Navier-Stokes equation. My question is how I should add the body force term F into the equation? The term F is listed in the...
View Articlesimulating vibrations of cantilwever in fluid environment
Hello I want to study the dynamic behavior of the cantilever vibration's in the fluid environment , but when using FSI module i am simulating, an error is coming "mass matrix is zero" .... can anybody...
View ArticlePLASMA SIMULATION ERROR
Hi, I'm trying to replace only Ar-type plasma with He-type in one of the demo models (using cross section files), but the error occurs during execution process as described below:"not convergence at...
View ArticleOpen Boundary Condition in Mathematics module
Hello, I have built a 3D Heat-Air model of an air-permeability defect. Basically, air is flowing from the heated volume through cellulose insulation to the attic (not heated). Therefore, I see the...
View Articleconverting tetrahedral matlab data to mphtxt file
Hello, I am trying to convert attached matlab files to mphtxt file in order to import the geometry I have created in matlab to COMSOL. Actually, I have more complex geometry but for now I am trying to...
View ArticleHow to open Femlab 3.1 file (.fl) in COMSOL 4.3 ?
Hi All; I got an issue. How can I open .fl file extension (Femlab 3.1 version) in COMSOL 4.3. Because COMSOL 4.3 use .mph file extension. Thanks
View ArticleTransmission and Reflection of a Three layered Structure
Hi All, I had designed a three layered structure. Using PORT 1, I excited the EM wave from the top of the ITO(Indium Tin Oxide) and placed second port(PORT 2) at the bottom of Ag(Silver). I had...
View ArticleGas flow in microporous media
Dear all, I', trying to depict the speed profile of a rarified gas through a microporous structure. However, until now i'm using Comsol 4.3 and the Free and Porous media flow module that i think it...
View ArticleRunning two GUI's to utilize remaining memory
COMSOL Community: I currently have a frequency-swept simulation running that comprises 30GB physical /41GB virtual memory, off of an 8-core, 128GB system. Even though a sweep in off-normal incidence...
View Articlepseudo 1D lithium cell model
Hi, I'm a student self-learning Comsol for my project and I'm trying to model a 1d lithium cell using the general form PDE as an exercise. 1D lithium cell modeling as mainly 2 part : transport of...
View ArticlePhase transformation with thermal hysteresis
Hi everybody, my colleagues and I are currently trying to model the austenite-martensite transition in shape memory alloys including the exchange of latent heat. Similar problems (regarding latent...
View Articlesingularity. error
Hello, Does anyboday know why I encounter the below error message in Comsol 3.5a? Error: Time 7.86913096623935e-007: Repeated error test failures. May have reached a Last time step is not converged....
View Articlemeshing error
hi, i got following error several times with different models while meshing. 'failed to respect boundary element on geometry edge'. may i know the reason behind this?
View ArticleSimulating piezoresistive effect in COMSOL4.1
Hi I want to see the resistance change of a silicon beam due to piezoresistive effect when it undergoes stress on its terminals. Can anyone tell me how I can set the piezoresistive coefficient in...
View ArticlePolynomial Issue with User-defined Variables
I have a 2D rectangular geometry that has porosity and permeability values dependent on x-coordinate. Polynomial expressions are used to define the local porosity and permeability. However, COMSOL does...
View ArticlePiezoresistive Coefficients
Hi I want to find out the sensitivity of my piezoresitive cantilver beam. In order to do that, based on the equations, I should have the piezoresistive coefficient (Pi-1): Delta-R/R=(PI-1)*maximum...
View ArticleProblem with Heat Source temperature dependence
Hello, I am trying to simulate pulsed laser heating of silicon wafer. I am using heat transfer module. My problem is 2-dimensional - my wafer is a cylinder and laser is above the center of it placed...
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