Extruding a hexagon polygon
I want build a prism with a hexagon cross section but am having some issues. I have drawn a hexagon polygon and tried to extrude this but it doesn't seem to be working. Any suggestions would be greatly...
View Articlehyperelastic material in contact with a rigid material
I'm trying to model the stresses in a hyperelastic material as it's removed from a highly rigid material (which is acting as a mold). I've set up a time-dependent model with the two materials, a...
View Articlehelix with rectangular cross section 2
Hi, I was following the thread re: helix with rectangular cross section and downloaded the file helix.mph. By fudging the parametric values, I almost get what I need except the the major radius appears...
View ArticleFailed to find a solution for the initial parameter. Multigrid canceled....
Hello everyone, I'm having a problem in my simulation, where it does not converge and return me this menssage when I cancel the simulation."Failed to find a solution for the initial parameter....
View ArticleEquation 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...
View ArticleEigenfrequency Problem
Good evening, I'd like to know if there's a way to find the highest, maximum , eigerfrequency of a structure using COMSOL.
View Articlechanging 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...
View ArticleProblem 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...
View ArticleError: 7161 The mass matrix is zero - resolve
Respected sir/ma'am, I am trying to simulate a Nano ElectroMechanical Switch(NEMS) using the following modules:a)solid, stress-strain, b) Moving Mesh, and c)Electrostatics. When i run the solver, it...
View Articlefailed to evaluate variables
Hi , I am building a 3d model of fluid flowing around a wafer using 4.3a. The following error occured when I tried to plot the pressure on the edge of the wafer. Cannot ecaluate expression. Failed to...
View Articledifferent physics with different meshes in 3D
Hello, I work on a casting model with a phase change in a metallurgy process. The 2D-axy model works fine and i begin the 3D model. I work on a 3D coupled problem with different physics: mf for...
View ArticleElectric field between electrodes
Hello I am trying to make a very simple model to calculate electric field between two electrodes in water facing each other(using electrostatics module). I set for the electrode boundaries opposite...
View Articlemodeling nanostructured organic solar cell with Comsol
Hi,how can I modeling Zinc oxide nanostructures organic solar cell in which include the effects of optical interference, exciton diffusion, charge separation via the formation of polaron pairs, and...
View ArticlePiezoresistive modeling
Hello all I want to simulate a piezoresistive beam with Comsol. I was looking to find an example of piezoresistive modeling to find out what module they usually use and how are the settings but i...
View ArticleProblem 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...
View ArticleMie 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...
View ArticleNew "Introduction to COMSOL Multiphysics" book now available
Hello, We are pleased to announce that a new version of the "Introduction to COMSOL Multiphysics" book is now available for immediate download...
View ArticleHow 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...
View ArticleProblem in my Results
Hello everyone, I'm having a problem simulating a cylinder of copper. The surround of it is a cube with PML and scattering condition. But my results (attached) seems a little strange. Can anyone help...
View ArticleOutput 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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