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How to calculate the confinement loss of the photonc crystal fiber

Hi, I am using the RF module to do some calculations of fiber. And I don't know how to calculate the confinement loss in fiber. I found that some people said the PML will be used to do this on this...

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Expression for Sherwood Number

Hi all, I'm looking to use the Sherwood Number for grid independence of a mass transport simulation, but am unsure what expression I should use in the plot. Has anyone ever written one before, or have...

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Can't see geometric block when transfer a model from Matlab to Comsol

Hi all, I am running Comsol ver. 4.3 build 4.3.0.151 and Matlab 64 bit ver. r2012a. I want to build a model in Matlab, to run it and then transfer the model from the Comsol server to Comsol client. I...

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Sphere-Sphere Forces

Hello. Firstly, greetings to everyone, I am new here. So, I am trying to build a model based on this article:...

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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...

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Poroelastic waves - acoustic module - material definition

Hi, I would like to model a poroelastic material with the acoustic module. However, can you tell me how I can link my parameters to material proporties. My parameters are : - porosity - tortuosity -...

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Newbie needs help seting up ramp function as voltage source

I am new to comsol and cannot figure out how to assign a rect function as the input source to a strip of copper. I subsequently need to study the thermodynamics (which I have successfully done in...

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capacitance of a parallel plate capacitor

These are the steps for my capacitor simulation 1. set two solid blocks (dimensions (25x1x20) ) 1 distance away from each other. 2. set a solid box (65x43x60) to surround the plates of the capacitor....

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Conductive Media DC(shell) + Electrostatics

hello I have been trying to couple the two application modes to find the electrostatic force on one boundary at a fixed voltage due to the voltage on a parallel boundary which has a variable voltage...

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3d laminar flow - solver problem: Segregated group 1.

Hi I´m simulating the convection heat transfer in a pipe. The external surface of the pipe receive solar radiation to heat the fluid that is flowing. I start my model with the laminar flow and after I...

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import a bmp image into COMSOL geometry

Hey, as stated in this webpage: http://www.comsol.com/products/formats/ Comsol can both read and write few types of images. However, when I tried to import a bmp image as my structure for flow...

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How to use parametric sweep by loading parameter values?

Hi, I have several parameters to add in study settings, as below: parameter: a1 a2 a3 a4 a5 first set: 1 3 4 5 7 second set: 2 1 3 6 4 ...etc. There are many sets, so I don't want to key in step by...

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Comsol not following ideal gas law or conservation of mass

Hello, I am currently working on modeling a high temperature hydrogen heat exchanger. I decided to start as simple as possible and just model the heat transfer into an axi-symmetric tube of hydrogen...

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Geometry optimization

Hello everyone, I´m modeling a simple heat transfer - structural problem, wher I have a 2-D rectangle with a hole in the midle. First I apply a Temperature load that produces expansion in the...

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Temperature Depdendent Electrical Conductivity acting weird.

Hi Everyone, I have two simple questions that I have been unable to answer after trying to work on them for a week. Please help me: 1) I have a very simple model (which I have attached), I am passing a...

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Cluster computing got stuck :external progress scheduling

Hi,Ihave recently setup a cluster and i had comsol 4.3 on the head node,and i had the installation forder shared, model working directory shared. However,when I am trying to submit a batch job,using...

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when to use parameters, variables, and functions

Hi All, Considering global values for now. It seems clear to me when to use parameters - any value that is independent of the independent or dependent variables. But when is it appropriate to use...

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Thermoelectric Effect - Adding the physics

Hello, I'm working in a project on thermoelectric generator. As 'Thermoelectric' physics interface,is not in the physics area/physics list, I was trying to add the physics using the steps given in the...

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parametric sweep

How to add parameters for the circle centre coordinates, and update parametric sweep settings , for change the distance between the two coils -- kishore Naik Mude

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difference in simulated stress and strain

Hi, I simulated stress for a 2D Silicon structure using "thermal stress" in COMSOL, the simulated stress values are quite consistent with my experimental results. however, when I look at the simulation...

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