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...
View ArticleGenerate and plot 3D solution, given 2D solution
Hi all, I'm using weak-form modeling to solve for a vector field u(x,y,z). The vector field has 3 scalar components u1, u2 and u3. I know the functional form of the solution in the z-direction; it is...
View Articlemeshvol
Hello, I'm looking to extract the area/volume of each mesh element of my model. I then discovered the quantity meshvol. However I'm not exactly sure what this gives me: using meshvol I get a scalar...
View ArticleSimulation of a wireless power system
Hi, I am trying to simulate a wireless power system between two coils. The transmitting coil is connected parallel to a electric circuit consisting of a capacitor and a voltage source in parallel. I...
View ArticleParticle Tracing Module
I am using COMSOL 4.3a and I am having trouble with the particle tracing module. I have built a geometry in which I solve for the Electric potential. I now want to apply a Dielectrophoretic force on...
View ArticleMoving top hat heat source
Hello, I'm trying to create a moving heat source with the energy profile of a top hat. So far I was able to move a circular heat source with a 'waveform' function. But I only managed to create a...
View ArticleShape optimization of radiating plate
Dear all, I'm currently optimizing the shape of a vibrating plate in an closed hollow cylinder filled with air to get an as straight as possible wavefront. I model it 2D axisymmetric and make use of...
View ArticleAccuracy of Simulation
Dear all, I am currently working on a complex micro mechanical structure. I simulated this structure in solid, strain-stress module. But I am not sure about accuracy of my simulations. Is there any way...
View ArticleHow to input this equation in PDE module
hi, all I want to construct a 3D model in PDE module using the following equation. I have read the help file several days, but can not figure out how to do this using either coefficient form or general...
View ArticleHow to calculate/indicate revers wall shear stress in Comsol?
Hello, I calculate the flow in arteries and I would like to show that for some time steps the wall shear stress has the opposite direction, for example in the curves, branches, etc. For the straight...
View ArticleResources for plasmonic wire grating
Hello All, I am trying to remodel the device in the 'plasmonic wire grating' example by varying diameter and material of the wires. As a background reading I wanted to read in depth about plasmonic...
View ArticleHow to set the remanent flux density in a simple magnetic force calculation?
HI everyone, I'm a starter using the comsol 4.2a. And I would like to simulate the magnet force on an iron bar from a permanent magnet. The model is built and it works, but the simulation result own a...
View ArticleDesign of Superlens in visible range using Metamaterials
Can somebody help me with designing superlens in visible range using Metamaterials..
View ArticlePoisson-continuity coupled equation
Hello, I try to model the corona discharge in wire-cylinder geometry governed by the equations: nabla (V) =- rho/epsilon0 (Poisson equation) and grad (rho) * grad (V) = rho ^ 2/epsilon0 (equation of...
View Articlecomsol error Failed to evaluate variable.
I have this error, see the attached file. Can any one help me quickly, please ? Thanks.
View Articleexporting parametric sweep analysis
Hi I am simulating a fibre using parametric sweep option where parameter is frequency. I am able to export the data for one frequency in a file but not for all in a single file. Can anybody tell me how...
View ArticleThin Film BAW Composite Resonator simulation in COMOSL 3.5a
I'm currently engaged in the simulation of FBAR device in COMSOL 3.5a, and want to use this model. However, "in the model library", I find that the admittance of electrode is defined as...
View ArticleHeat Transfer
Actually, I need to give boundary condition to one of the part of my system. At that part, I will use cryocooler of capacity 1 W at 4.2 K, how can I give this boundary condition to particular part. My...
View ArticleModel couplings: Integration vs. Summation over nodes
Hello, I am working with two modules Structural Mechanics and general form PDE as coupled. I need a model coupling to define an integration. When I choose "Summation over nodes", my model works fine,...
View ArticleTransport of concentrated species, Membrane gas separation
I've attached simplified model describing transport of the one component through membrane. I've made it simple to make you catch a problem easily. In my advanced model I'm using Laminar Flow physics...
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