Effect of prestress on eigenfrequency
Hello, I am trying to model the effect of the prestress on eigenfrequency of a vibrating string (clamped at both end with a prestress) The problem is that I am using 3.4 here. Would you please let me...
View ArticleMagnetic Force on an armature
Hello I'm dealing with a very simple problem that has been very frustrating for me! I would appreciate if any one can assist me with that. I'm modeling an E-shaped core in 2D magnetic field module. It...
View ArticleLinking a Porous Media Flow to a Transport of Concentrated Species
Hello, I have created a chamber that has sugar water running through a compartment and carbon cloth modeled by a free and porous media flow physics. I also want to create a transport of a concentrated...
View ArticleCoupling B/W two solid stress-strain modules
Hi all, I am trying to model a 3D structural mechanics problem with two separate solid stress-strain modules coupled together at the interfacial boundary through equal displacement boundary condition...
View ArticleGeneral Projection Bulk Temperature Example & Question
Dear all, The following model may prove useful to somebody (other than myself) who wishes to calculate the average of some scalar value as a function of axial distance. In this case it's the bulk fluid...
View ArticleTypical fluid-structure interaction model
Hi I am new and struggling to start a simple model. I have been playing with blood vessel model from the model library. I would like to look at the vascular behavior when blood vessel is impacted by a...
View ArticleInduced charge on a surface by a charged object at different relative positions
Hello, I am new in COMSOL and I was wondering if anyone could five me any idea. I want to simulate the evolution of the induced charge on a surface as the relative position to a charged object varies,...
View ArticleElectric potential boundary on thin structure
Hi! My model contains a thin film with a thickness of 30 nm. I have applied different potentials and grounds on the thin boundaries of this film without any problems, but now I'm trying to apply these...
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...
View ArticleCircumferential direction
Hi My equations are in default cartesian(x,y,z) coordinates. But my geometry is circular and I want to see the temperature distribution only in circumferential direction. It would have been better if I...
View ArticleWaveguide amplitude errors, scattering boundary condition
Hello everyone! I am modeling a waveguide with the purpose of verification, but I am getting high errors in amplitude when the length of the waveguide is not a multiple of the wavelength of the...
View Articleaccuracy in evaluating refractive index
Hi, I am using RF module > perpendicular mode in order to simulate the distribution of modes and get the refractive indices, when I use related m.file of the geometry ,I get refractive indices with...
View ArticleEvaluation of calculated parameters on a specific grid of points
Hi all, I am doing some calculations on solenoid magnets and would like to get the magnetic flux density vectorial components at specific points of a helix that are defined in an external file. I would...
View Articleadvice for simulation set up or suitable tutorial (3D stress distribution...
Hi All, I am trying to help my fellow Orthodontics to showcase COMSOL's ability to simulate one of his problem. But I am struck and getting inconsistent results. The simulation is very basic and...
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 Articleabout heater simulation in the room
Hello! I am use comsol 4.3a , and use the non-isothermal flow physics to simulate the heater in the room. And the room has a door , and I want to set the door is open, and it is connect to the...
View ArticleOptimal parameters in a GMRES solver with GMG preconditioning
Hi, I am solving a high-frequency 3D acoustic problem with millions of DOFs. Documentation suggests to use a GMRES solver with GMG as a preconditioner. However, it gives very little details on the...
View Articlefailed to evaluate jacobian in using velocity field in fluid particle tracing
Hi, I have tried to edit drag force's equation view in fluid particle tracing(fpt). COMSOL for example, uses "model.input.u1-fpt.vx" for relative velocity in x direction but when i use it in my...
View ArticleFlow between parallel plates
Hey, I am trying to model flow between 2 parallel plates both of which are moving towards each other. The equations applicable are Continuity and Navier Stokes. However, I am quite not able to find the...
View ArticleHeat transfer from the pipe to surroundings
Sir, We found three options for "Wall Heat transfer" in "Non-Isothermal Pipe Flow" namely 1. Temperature (nitf/nitf) 2. Temperature (nipfl/nipfl) 3. Userdefined. (with an option to check "Take average...
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