Eigenvalue analysis " Mass matrix is zero"
I am trying to run a Static Eigenvalue analysis of a structure . My model is a stone-building , so i just enter the properties of the material and the constraints . When i solve the problem appears the...
View ArticleError: 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 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 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 ArticleThermal expansion model
I am trying to examine the stress distribution in a SiO2 film coated on a thick Si sample with a small Al bump on it, all heated to 700 K. I thought I built the model correctly, but the resulting...
View ArticleModel coupling from 2D-axi to 3D in fluid flow
Hello^^ I'm simulating an electrostatic precipitator, as uploaded picture. In this, the geometry can be considered as a symmetric cylinder, so I think the laminar flow module can be solved in...
View Articledispalcement calculation???
hi, i am designing a pressure sensor......i have got displacement of 0.28nm for applied pressure say 10000 pa...how can i know whether it's correct or not... how are pressure n displacement related to...
View Article3D waveguide, compute electromagnetic field
I want to view the electromagnetic field (in particular the norm of E) of 3D waveguide. I haven't experience in a 3D waveguide, I have simulate always a cross-section of waveguide. First of all I...
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 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?...
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