Error: 7161 The mass matrix is zero - resolve
Respected sir/ma'am, I am trying to simulate a Nano ElectroMechanical Switch(NEMS) using the following modules:a)solid, stress-strain, b) Moving Mesh, and c)Electrostatics. When i run the solver, it...
View Articlehow can I use plasticity model in the poroelasticity module
I want to use soil plasticity model in the poroelasticity module? How can I add soil plasticity model into the poroelasticity module? I notice I can add soil plasticity model in the structural...
View ArticleRichard's Equation questions
Hi, I'm trying to use COMSOL to model water infiltration and evaporation in porous media. Few questions in this issue: 1) How do I define a boundary as open boundary for Evaporation. How do I define...
View ArticleEvaluation of Volumteric displacement
Hi all, I am modelling a diaphragm deformed under pressure loading in an axisymetric model. I was wondeing if there is a way to evaluate volumetric displacemnt of the diaphrgam due to displacement....
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 Articlewhy does deformation remain same?????
hi, i have designed a pressure sensor... i am getting different displacement values as output but deformation for all applied pressure is same....why is it so??? wat should i do to get the deformation...
View Articleout of memory during LU factorization ?
I use comsol multiphysics 4.2 to solve a model on my computer(with 2GB RAM), I get the error "out of memory during LU factorization", but when I put the same model into another computer(the same cpu,...
View Articlecontact modeling and time dependent analysis
Hello all, I am trying to model a time-dependent vibration problem (resonant vibration) with contact and I am having trouble solving the model. The contact is between the shaker and the object. I want...
View ArticleQuestion about Nernst-Planck Model
Hello, I'm a new user for Comsol 4.2. When I applying the Nernst-Planck model form my work, I added 5 species, c1,c2,c3,c4,c5 which zc1=+1, zc2=-1, zc3=-3, zc4=+1, zc5=+1 and set the 'from...
View Articlecharged particle deposition
Hi all, i'm trying to model (3D) an electrodeposition of nanoparticles under laminar conditions (fluid flow), but i've no idea....which module i should use. I'm using the comsol version 4.2a. any idea...
View Articlepartical tracing never works
hi i cant get particle tracing to work help pls. i have a simple 2d example with a rectangular with an electric field on it. the particle tracing modul doesnt show any interaction between the particles...
View ArticleScttering problem using comsol4.2
I wanted to calculate scattering absorption cross section and thereby extinction for a nanoparticle. I am not sure how to go for that in comsol4.2. Can anyone please tell a basic flow to accomplish...
View Articlethe free vibration of the cantilever
Hi everyone: The initial displacement D=1.05mm, is placed on the end of the cantilever beam, to solve the velocity response of the beam end. First, I select space dimension 2D, and add physics Beam,...
View Article2D coplanar waveguide Port Modeling
Hello everyone, I have a very simple 2 D model of the crossection of a coplanar waveguide (substrate in an air box, at the boundary between substrate and air I have lines for the metallization). I want...
View ArticleWeak Form Modeling and Multiphysics Coupling in RF Module
Hello All, I have some problems when using user-defined weak form PDEs and multiphysics coupling for 3D nano particles scattering in the RF module. Please find the attachment for the detailed...
View ArticleInternal error in geometry decompositon: problem with just 2 elements in model!
Hi Everyone: I am trying to build a complicated 3-D model with many channels and such but I ran into a problem very early on. I just have one block attached to one hexaheadron. I am unable to form a...
View ArticleFrom PDE to linear algebraic equations. Algorithm of solver
Dear Sirs, please advise me with my deal. I simulated a model in ACDC->Electric currents. As I can see there are some differential equations which FEM approximates into a system of nonlinear or...
View Articlemphgetu
Hi all. I am using Comsol with Matlab (version 4.0) for a time-dependent analysis. I have to process many data (there can be 1000000 degrees of freedom). It takes a lot of time to save these data and...
View ArticlePML v4.0
Hi all. I would like to use the PML for a time-dependent analysis in the Structural Mechanics Module (version 4.0), but it doesn't look to work well. Can you help me to implement the PML in my model?...
View ArticleSimulation of a wireless power system
Hi, I am trying to simulate a wireless power system between two coils. The transmitting coil is connected parallel to a electric circuit consisting of a capacitor and a voltage source in parallel. I...
View Article