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ERROR: FAILED TO EVALUATE VARIABLE JACOBIAN, Variable: Freq

Hi, I am getting the following error: Failed to evaluate variable Jacobian. - Variable: freq - Geometry: 1 - Domain: 1 2 3 - Feature: Stationary Solver 2 (sol2/s2); - Error: Failed to evaluate variable...

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Generate report with 4.1

I am wondering how to generate a detailed report like the one below in Comsol 4.1.resource.npl.co.uk/docs/scienc...symmetric/microdisk_report.pdf Couldn't find anything comparable in the documentation.

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complex current density

Hi all, I'm working on getting the frequency dependent conductance and susceptance (real and imaginary admittance) of a simple resonating PZT block using the Piezoelectric Devices physics. I seem to be...

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Rotate Graphics Window 90deg in 2D Axisymmetric

Hi, Is it possible to rotate (90deg.) the graphics window in 2D axi. so the z-axis is horizontal and the r-axis is vertical. Thanks!

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piezoelectric cantilever coupled with an external electric circuit

Hi Ivan, we're still working on piezoelectric cantilever coupled with an external electric circuit. We obtain very good results in the case of open circuit. When we introduce a load resistance the...

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Piecewise function implementation

I"ve tried to implement the material properties, more specifically refractive index, in a 2D model of lens. Is there a way to define a piecewise function that describes the refractive index of all...

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Parallel progamming using COMSOL 4.2a

Is it possible to install a license in a cluster? I've already have a Floating Network License (FNL) from 4.2a version installed in a computer that runs in Windows. Could I install the same license on...

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Multiple physics with same dependent variable

I am working on a model with multiple physics, Electrostatics and Poisson's Equation and the dependent variable in both physics is Electric Potential. How do I set both the dependent variables using...

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Coupling of Electrostatics and Nerst plank equation

Hi, I am trying to solve two equations simultaneously as follows 1) Div(Grad (V)) = - rho/eps 2) Div(D*Grad(C) - Z*u_m*F*C*Grad(V)) = 0 where V is voltage ,rho is space charge density, eps is...

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Modelling Compression of Material at a Rate

Hello, I am a beginner to COMSOL 4.2a and I would like to build a simple model where a material (a cylindrical block of polymer) is compressed at a rate of 10 mm/min. Using Solid Mechanics, I was able...

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electric field remains the same irrespective of the material used!!!!!

Hello friends, Am trying to simulate the electric field between two circular electrodes placed inside a circular dielectric field.Irrespective of the change in circular dielectric material the electric...

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Microwave oven waveguide configuration

Hi everybody, I am trying to simulate a microwave oven using COMSOL, but I'm still a bit confused about configuring the waveguide. What is the difference between Transverse Electric (TE) and Transverse...

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How to calculate force on a material???

Hello friends, Am trying to calculate force on a circle for an applied voltage, which physics should i choose?

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How to add AC source

Hi, In the simulation, a spiral antenna is excited by AC source in RF module. Physics is emw and study type is frequency domain. I want to use a square-wave AC to excite two terminals of antenna. My...

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electrospray simulation

Hi, I'm trying to simulate an electrospray experiment using comsol 4.1 in order to see the formation of droplets leaving a needle to a plate. A high voltage is applied on the needle and the plate is...

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how to plot the velocity profile between any two points in Comsol 4.2

In comsol 3.5, when I want to get the velocity profile from (0,0) to (0,4), I could use postprocessing--> cross section plot parameters --> line plot, then I can input cross section line data....

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How to use parameters between different physics?

Hello, my name is Wang Jiujiang from University of Macau. I am using COMSOL to simulate a capacitor, after I simulated using DC voltage, I want to add AC voltage. After I add a physics--circuit and...

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Modeling 3D Induction heating with Frequency-Stationary simulation

Hi, I am trying to simulate induction heating due to a spiral inductor with different core materials. I want to perform a Frequency-Stationary analysis. I have the following problems: 1. The usual...

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Vibration of a cantilever beam

Hi, I am trying to model a beam oscillating under external vibration condition. I have kept one end of the beam fixed. I have tried applying different kind of boundary conditions to solve the problem....

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does a periodic boundary condition for u implement inflow u (boundary1) =...

Dear everyone, I have a question about the implementation of periodic boundary conditions for fluxes, so that the inflow through one boundary equals the outflow through the other. In comsol 3.5, this...

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