Measuring the temperature at a point
Sir, In a non-isothermal pipe flow model, we have specified wall heat transfer with external temperature as 293.15K and the check box for taking average from adjacent domains is also checked. After...
View ArticleFailed to evaluate variable in particle tracing module
Hello! I'm trying to simulate particle temperature in particle tracing module. But, when I try to plot a line graph of particle temperature, I see this: Failed to evaluate variable Variable - mod1. Tp...
View ArticleScatterer on substrate, RF module
Dear All, Probably some of you RF module users saw module “Scatterer on substrate” in model gallery. I have question about that, and I have question about total field formalism in generally. So, basic...
View ArticleMoving items relative to each other
Hello, I am a beginner user, and I was wondering if anyone could help with my problem. I am trying to calculate electrostatic forces between objects, as one is moving relative to another. Must I create...
View ArticleMapped mesh in 3D
Dear all, 1-I trying to mapped mesh a solid in 3D, but it sends me an error message "Error: 7161:The mass matrix is zero" when i try the eigenfrequency, and yet if the default mesh does not send it....
View ArticleError with mesh change
I made a simple eigenfrequency study with a beam using a Free Tetrahedral mesh and it worked fine. But, when I change the mesh type to Mapped and define the size of elements to 5mm, I received an error...
View ArticleHyperelastic Material Models
Are there any talks about COMSOL implementing other hyperelastic models like Yeoh, Ogen or Arruda-Boyce? Thanks.
View ArticleEigenvalue 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 Article"Failed to compute elastoplastic strain variables" Help Please
Hello, I am an absolute beginner at COMSOL Multiphysics and I am trying to model the effect of the movement of soil on a steel pipeline buried in it. I have attached the model file with this post. I am...
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 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...
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