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Output pressure of the transducer in frequency domain

Hello,everyone I'm doing research in capacitive ultrasonic transducer. I use the electromechanic model and want to observe the output pressure in the frequency domain. Now I can add the biased voltage...

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Gravity volume force in non-isothermal laminar flow

Hello I'm trying to simulate non-isothermal laminar flow through a tube, and I use 2D-axisymmetrical to decrease the computing time. The model works fine with laminar flow and heat transfer, but when I...

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connecting solid and beam elements.

Hi, how can I use the beam element to act as a shear connector between two solid elements.

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Equation Based Modeling in structure mechanics

Hi All, While solving equation based structure mechanics problem i encountered the following error message- - Undefined value found. - Detail: Undefined value found in the stiffness matrix. -There are...

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Eigenfrequency Problem

Good evening, I'd like to know if there's a way to find the highest, maximum , eigerfrequency of a structure using COMSOL.

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changing boundary cond. with time

Hello, I want to ask for advice how to change boundary condition in time. E.g. I have exact temperature on boundary for 3600 sec. and after this time, I want to change this boundary to insulation. I've...

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Problem with meshing in a microfluidic channel.

Hey all, I am trying to simulate the deflection of a half-sphere, with ALE Fluid-structure interaction, stuck on the bottom surface of a microfluidic channel (height = 50 um and width = 300 um) and it...

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negative concentrations with high reaction terms in biokinetic models

Hi, I am using a biokinetic model based on the ASM (activated sludge models) to simulate water contaminant removal in a gravel filter. This kind of models consider the degradation of the influent...

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Mie scattering in 4.3

Hello, I have already seen some discussion about mid scattering of a gold nanosphere. But I the discussions I have consulted, no one has yet implemented a mie scattering program in Comsol 4.2 or 4.3...

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How to set initial velocity in level-set method two phase flow for one phase

Hi guys, I am trying to set the initial velocity for a droplet as fluid 1, how can I set an initial velocity for the bulk of fluid (for example the the continuous phase or the drop) in level set...

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Controlling my own boundaries

I am modelling a closed tube of air in 3D with a heating plate at one end of the tube. I have measured the temperature distribution across the heating plate as a function of time and location and would...

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Simulation of leakage flux from transformer

Hello. I've tried to simulate a quantity of leakage flux from transformer by using COMSOL 4.3a. To do this, I made a simple transformer model with LiveLink for AutoCAD.(I want to attach mph file, but...

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Harmonic Load

Hey, I'm new to COMSOL and I have a few questions about it. I'd like to do a Frequency Response Analysis of a structure with a harmonic load ''shaking'' it with a pre-determined force and frequency ,...

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Temperature dependent creep analysis!!

Dear all, could you share your knowledge on temperature dependent creep analysis!! I’m using COMSOL 4.3a to see deformation pattern. In this model, I apply Linear Elastic Material with Norton creep...

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How can I find the flow velocity of a specific coordinate point

Dear all, I would like to ask how can I find the flow velocity of a specific point (x=105, y=2.5) in my channel (it is shown in the picture). In the graph, if I click at any random point I got 3...

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Type in the divergence of a gradient, manually.

Hi, I am trying to model some thermo diffusion where I need to type: div(-“factor”*grad(temperature) ) , manually. Does anyone know where to find perhaps a list of the syntax for these operators? Thank...

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Automatically parameter increasing

Dear friends, I have a simple 2D rectangular model, I want to measure some acoustic properties in my desired frequency range, for specific height of model it's easy, but I want to check a range of...

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Adapative Mesh Refinement with Mapped Distribution

Hello, I'm using Comsol version 4.3 and, for some reason, when I try to use adaptive mesh refinement in the Stationary Solver's extensions, it claims I can only use triangular mesh elements for it. I...

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Warning: Edge is much shorter than the specified minimum element size.

I am trying to mesh a 3D integrated concrete masonry block. The geometry is somewhat complex but the idea is that it is a layered apparatus: brick, foam, brick. I am trying to measure the R-value of...

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Magntic field analyses using current excitation

Hello, I have started to use Comsol this week and have done some examples, but when I try to simulate my model I hit some set backs. The model has 16 electromagnetic poles with a pair of coils in...

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