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How to calculate Extinction efficiency in comsol35a?

Dear Users, I am new to comsol. I have tried the example of a gold nanosphere in RF module. I have obtained directly the scattering cross section, extinction cross section and absorption cross section...

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Conversion: Comsol mesh to Comsol geometry

I have a question concerning the possibility to convert Comsol mesh to Comsol geometry. For instance, I have a Nastran surface mesh which has been imported into Comsol mesh but I would like to use this...

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Problems while using Interpolation function

Dear colleagues, I am trying to use the data output from a Matlab program as a source in my coefficient form PDE using the interpolation function. The data is being distorted by the interpolation...

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Solving Self - Consistent Schrodinger and Poisson with MATLAB and COMSOL...

I'm a COMSOL 4.2a user. I need to solve 2D self-consistent Schrodinger and Poisson equation. Thus, I need to feed the potential values and the wavefunctions to the Schrodinger and Poisson equations as...

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Identifying the eigenfrequencies of a shell sphere

Hello, I am new to Comsol and I was asked to identify the eigenfrequencies of a hollow sphere of 100um diam. and about 3 um thickness. I started by using 2d axisymmetric analysis->solid mechanics...

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Time Space dependent Interpolation function

Hello! I want to use a velocity boundary solution u(x, t) from one physics in another physics. The timesteps, the mesh and the geometry are equal. I use the Laminar Two Phase Flow, level Set physics in...

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Define a Mixed (cauthy) boundary condition for Richards Equation(subsurface...

I read some paper, in the old version of COMSOL, we can choose a Mixed boundary condition (mix of Dirichlet, Newman and Cauchy conditions). in order to automatically transfer the boundary condition...

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Conjugate heat transfer pipe flow

Hello, I am trying to simulate a very simple laminar flow inside a pipe problem with a constant temperature at the walls. I have a cylinder made of water(liquid), and where one part is kept at a...

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Installation problems on Ubuntu 11.04: Failed to load libjvm.so

Hi, I have problems installing COMSOL 4.2a under Linux. I mounted the .iso file as indicated, but when i run setup, i get the following error message: Failed to load the JNI shared library...

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How to display current density in thin metallic layer difined by transition...

Hi to all, I'm working with the RF module to simulate response of metamaterial which consists of split ring resonator (SRR). The SRR is made of thin metallic layer. To model the layer within Comsol I'm...

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Natural Free Convection

Hello, I'm attempting to model the temperature rise above ambient over the period of one day within a sealed concrete trough buried in soil with its top exposed to outside air. I have successfully...

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Finding the location of the maximum of a variable

Dear Comsol Community, I am looking for a way to find the location of the maximum of a variable. Getting the maximum value is easy, but so far I have not been able to get the coordinates of the...

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Problem: Oil Droplets Seem To Dissolve In Water (Two-Phase Flow, Level Set)

I have a problem with my "Two-Phase Flow, Level Set" simulation in COMSOL 4.2. I am trying to simulate the formation of oil droplets in water by hydrodynamic flow focusing. The water and oil are...

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can extract such kind of coordinations to build the model?

Hi, everyone, I’m building a heat transfer model, so the dependent variable is the temperature T. During the model, I want to obtain the location or coordination (x,y) where the temperature is equal to...

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non uniform heat flux

Hello all, I'm trying to model simple 2D conduction model in a slab. What I want to do is use a non-uniform heat flux for a boundary condition. I already have the heat transfer coefficient distribution...

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Problem about Joule heating and thermal expansion

Hi I want to inject ac current (amplitude is fixed) to a silicon beam and hope to see maximum expansion when the ac frequency is at half of the mechanical resonant frequency of the beam. I tried using...

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Conjugate heat transfer Interface boundary condition

Hello All, I am new to COMSOL. I am trying to solve a 3-D conjugate heat transfer problem with volumetric heat generation in the solid domain. The problem is more like solving for a temperature profile...

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How to change font size in the help of Comsol?

Hi, I am using Comsol Livelink for Matlab and I open the Comsol help from Matlab (using 'mphdoc' command). The help browser that I open looks exactly like the help browser of Matlab and even give as...

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Define a selection from the solution

Hi, I am solving a two-phase system and I want to know, how can I calculate the time-dependent rise velocity of the bubble (in the file below)? In my case the domain selection is not possible because...

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Extract Data from a Parameterized Surface

Hello, In my comsol model I would like to extract the electric and magnetic fields on the surface of a sphere. What I do now is the following: 1) I define a Parameterized Surface in the Results>Data...

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