Duplicate variable name
Hello all, I got some duplicate variable name error when computing my model(see the attachment), which including the piezoelectric device, laminar flow and deformed geometry. Should I use the physics...
View Articleco-efficient of thermal expansion
Hello evrybody, Can anyone help me to know if I can input my co-efficient of thermal expansion as a function of Stress and Temperature or not. And if possible how to do that. Thank you.
View ArticleOutput pressure of the transducer adding Vac + Vdc
hello, I 'm working on a capacitive transducer, using the electromechanics(emi) model. Now I want to observe the output pressure of the transducer in the frequency domain and I add a voltage V=Vac+50...
View Articleerror in statonary analysis of a biased resonator
Dear comsol community, I'm working on comsol4.2a , I would be glad if i can get a solution for my following two queries: 1) I have gone through the modelling instructions given in the 'Stationary...
View Articleplot
Hi I simulate the mode profile of the rib waveguide. Now i want to plot the normalised intensity(arb unit) in the x and y directions. Do you know how can i do this?what is the arb unit? how can i find...
View ArticleResonance frequency of beam (calculation+plot)
HI I want to calculate and plot resonance frequency of cantilever that I designed in MEMS module. Based on the previous discussions here I understand that I should do the study in "Eigenfrequency" and...
View ArticleOut of memory during LU factorization
Hi there, I am a new member in the COMSOL community. I am trying to solve a simple 3D problem having diffusion and chemical reaction within the subdomain. However, I am getting this message "out of...
View ArticlePiezo Loading
I have a 3D piezo model and the output is currently a floating potential. This tells me the theoretical unloaded voltage gain. I'm working on possibly using a global equation of a simple ohms law...
View ArticlePlacing a finite element model into an electrical circuit in COMSOL 4.1
Hello, I have recently made the switch from COMSOL 3.5a to COMSOL 4.1, and I am currently unable to do things that I used to be able to do very easily, namely placing my 3-D model (drawn and defined in...
View ArticleMark my experimental values to the curve point in the plot window of COMSOL
Hi Everybody The purpose of my question is to compare the theoretical curve obtained on COMSOL with my experimental values on the plot window. I have a curve point on the plot window. I have a few...
View ArticleError message "Cannot import a 2D geometry into a 3D sequence." in RE
Hi! I have a 2D Reaction Engineering modell and want to add some more physics through the Synchronize with Comsol Multiphysics. I have imported my 2D geometry to the RE model. When I then import the...
View ArticleHow to Convert a 2D model Into 3d model
I want to know that how i can convert a 2D model into 3D model for simulation. -- Vineet Bansal Project Associate, NPMASS Electronic Science Department Kurukshetra University, Haryana
View Article3D Poisson equation problem coupled with Nernst-Planck equation
I used coupled Electrostatics physics and Transport of Diluted Species physics to simulate this problem. The source term in Poisson equation is the difference between cations and anions. Usually, the...
View ArticleStructural Mechanics Equation System
I am trying to understand how my structural mechanics model is computing its solution. The model solves and gives me a reasonable solution. However, I don't understand how it is arriving at its answer....
View ArticleSloshing Tank with FSI
Hello All I calculate the waves of a water tank and then damp with a structure the waves. At the beginning I start with a single excitation an then wait and just let the gravity do the job. My model is...
View Article2D geometry but illuminated from below
Hi, I want to create a 2D geometry but illuminate it from below, or out of plane, with a plane wave. Whenever I try and set the Background Field as exp(-i*emw.k0*z) (in x direction) I get errors as it...
View Articleproblem with port boundary condition
Hi, I am trying to simulate a coupler so I need to set a port as inport and I have to select "wave excitation at this port " check box but it's inactive. How can I activate it? Thanks, sara
View ArticleFlux units in surface reaction interface module, and modeling of surface...
Hi, I am trying to model a bulk - surface reaction-diffusion system (diffusion in the solution, diffusion on the surface, and adsorption/desorption which couples the two together). The system has a...
View ArticleError: Failed to compute elastoplastic strain variables
I am using solid mechanics and Darcy's law modules. In the solid mechanics, I add soil plasticity model and use D-P model, but calculation is ending by this error. Could you tell me what is the problem...
View Articlesolver settings
Hi I'm using two physics piezoelectric and moving mesh. I want to change the thickness of the PZT layer using moving mesh and want to calculate the voltage value for each thickness. how to do it in...
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