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ion motion in DC plasma

Hej there, I have a problem with the DC discharge plasma. I need to simulate a plasma in a tube with a gas flow. The plasma is generated through some decay reaction in the tube (in reality due to...

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Unidirectional coupling of a time dependent study to a stationary study

Hello, I am using structural mechanics module and a stationary study to calculate stresses and strains in a simple 2D axi-symmetrical model. The model has a thermal expansion node. I have another study...

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3D Modelling of a pair of cylindrical magnets

Hi! I need to model the magnetic field lines when a pair of cylindrical magnets of 1.5T are placed at a distance between each other. How do I go ahead? Please help! PS: Am a beginner. Thanks!

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No change in a time dependend model. Where is the fault?

I tried a very simple model: = 3-D cylinder from = copper (from the builtin material library) with an = initial temperature of 293.15 K = insulated at all surfaces, with one = heated bottom surface at...

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Absolute tolerance convergence criteria for flow simulations.

Hey. Normally convergence criteria are divided into a relative and an absolute. Where can I find and set the absolute tolerance for my transient flow simulation. Thank you for your time

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Particle tracing: timing issues

Hello, I have created a simulation suite that calculates the electrostatic field of a given device and traces particles through this field. Since none of the available particle release nodes suited my...

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Error during multiphsics

Hi.. We are try to design saw delay line gas sensor, during the simulation we got error as- Fail to find destination boundaries or destination selection empty please help us to sort out this error. --...

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Measurment of mutual impedance of a dipole. Problem with results and derived...

Hello, I am using Comsol to model a dipole and a in a middle of permittivity 80 and conductivity 0. The model is a simple one and the study is in the frequency domain. The module used is AC/DC -...

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AC/DC

Hey. How can I view the field lines of electric and magnetic field? Thank you. Bye.

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Question on heat transport turbulence model

Hi, I am using the Non-Isothermal Flow (nitf) module and I have a question on the heat transport turbulence model. In the equation given by COMSOL, rho * Cp * dT/dt + rho * Cp * u . Grad(T) = Grad . (k...

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Time dependent fluid problem

Hi I am trying to model a time dependent flow of a newtonian fluid in 2D. The geometry I'm using has sliding walls which cause a flow to be established. The aim of using a time dependent simulation is...

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Placing 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...

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Java Runtime Environment error

Getting following error, A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0x0000003da3efbc6c, pid=6909, tid=46912497239488 # # JRE version: 6.0_20-b02 # Java VM:...

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COMSOL Releases COMSOL Multiphysics version 4.3a

We at COMSOL are proud to introduce version 4.3a of COMSOL Multiphysics to the COMSOL community See: www.comsol.com/products/4.3a/ This introduces: * LiveLink™ for Excel® * LiveLink™ for Solid Edge® *...

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Subsurface flow in heterogeneous reservoir......

Hello all, I am trying to simulate a model which contains square geometry and two circles(inlet and outlet). I am a new user of COMSOL and facing many problems like how to put inflow and outflow rate...

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Disk error while writing to to temporary file

When I try to open up larger COMSOL files I get this error. What does it mean and how can I avoid it? I have tried in two different versions of COMSOL (4.3b and 4.4) and get the same error no matter...

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Problem with Heat Source temperature dependence

Hello, I am trying to simulate pulsed laser heating of silicon wafer. I am using heat transfer module. My problem is 2-dimensional - my wafer is a cylinder and laser is above the center of it placed...

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Coupling of Drift Diffusion and Heavy Species Transport Plasma

Hello, I would like to simulate a cold plasma (Tritium ions/Electrons) in a tube in a high magnetic field. On one side of the tube there is a potential (some Volts) and on the side walls of the tube...

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electrostatic

hello all, I have a simulasion on COMSOL resolution of the equation of fish (Maxwell's equations) electrostatic My problem must solve this equation, we must obtain the charge density, current, electric...

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Frequency domain propagation, loss, refelcetion

Hi all Comsol friends, I am calculating the transmitted power loss for one 2-D waveguide, use intop2(emw.nPoav)/intop1(emw.nPoav) intop2 is the integration of output bounday. intop1 is the integration...

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