rigid particle carried by a channel flow
Hi I have to simulate the displacement and rotation of a rigid prticule in a fluid flow and I am not a professional on comsol. So, is there anyone who could help me? or if you have any examples of this...
View ArticleHysteresis loss Modelling of Inductor coil
Hello I have simulated inductor using AC/DC module and I have calculated the inductance and magnetic field around the inductor but now I want to calculate the hysteresis loss in the inductor. For that...
View Article"zero length" element
I am trying to model a bolt connection in an assembly. In order to do so I would like to place a node at the center of where the bolt hole should be (all bolt hole cutouts have been eliminated) and...
View ArticleDesign and Analysis of 2D Single Axis Capacitive Comb Drive Accelerometer
Dear Sir, We have been designed 2d Single Axis capacitive comb drive Accelerometer. when i computed electrostatics study to find capacitance i found a large difference between simulation and...
View ArticleEigen frequency????
hi, how can we determine what the eigen frequency of a designed structure is among a list of obtained frequencies..
View Articlephysical adsorption-which COMSOL module
Hi there, I am now working on a model about the absorption of solute by gold thin layer in a flowing cell. The absorption of solute by gold thin layer is physical adsorption. I want to know which...
View ArticlePerformance problems with Interpolation Function
Hello, I am using a 3d interpolation function with data from a large file (>100MB). When I execute a computation (e.g. an Eigenfrequency Analysis), it takes a long time (~15 min) before the solver...
View Articleheat transfer coefficients
I'd like to know more about the heat transfer coefficients present in the material library. I see that it depends from the surface temperature, from the temperature at infinite distane and from a...
View ArticleAnalytic function accepts only [m] and not [mm]
Dear all, I have a trouble using an analytic function: I get values only using the SI unit of measure, and not with the MPa one. The model is a first attempt of a welding simulation, and the analytic...
View ArticleOn microstrip impedance computation
Hi everybody, I'm a very beginner COMSOL user, I started just some few days ago with the 4.3a version and I need to build some microwave sensor models. I started trying to realize some very simple...
View Articleunit normal vector
Hello, I am solving a PDE using coefficient mode. I have a scalar filed, variable C, which has arbitrary boundary inside the domain (picture 1) that evolves with time. I want COMSOL to find the unit...
View ArticleOutlet for transient cases in two phase flow
I have problems converging a two phase flow with water and air. When the water exits the computational domain, I can see reflection of water. Also some cases diverge before the water reaches the outlet...
View ArticleScattering boundary condition and port with plane wave
Dear all, I want to simulate the periodic nanostuctures on silicon. now i am using comsol 4.3a version which is not supported PML with port boundary. for that i need to define the Scattering boundary...
View ArticleHelp understanding how boundary conditions for identity pairs work
Hello everyone, I’ve been reading through these discussions and the Comsol help guide, but am still having trouble wrapping my head around exactly how the boundary conditions for identity pairs work –...
View Article3D AC/DC simulation with motion? COMSOL 4.2a
Hello, I would like to model a 3D permanent magnet generator moving at a constant rotational velocity. My plan would be to use the AC/DC module combined with the Structural Mechanics>Solid...
View ArticleSolving a system of coupled PDE
Hi, I try to solve a system of coupled PDE with Comsol. Unfortunately, I have problems to choose a suitable solver. Details of my question and a model file are attached. I would be very grateful for...
View ArticleHow to couple pore water pressure to simulate triaxial test using Cam-clay model
Here are some questions I want to ask. Thanks! the figures are in doc file. Problem description: We want to simulate the behavior of soil sample from a trialxial test. The cam-clay model here is...
View ArticleIncorporating Lagrange Multipliers
Hello again, Thanks to the help of those on the forum I was able to incorporate weak constraints to get accurate flux calculations in my diffusion models. However, I am trying to understand how exactly...
View ArticleDefining dispersive material
Hi, I need to define a material that has Eps Real = 1 and Eps Imag = 2 at 0.1 GHz. How do I fit a 1st order model for this material? I have uploaded a screenshot of the dispersive curves for this...
View ArticleConcentrated Chemical Species
Hello All, I am in trouble defining the constraint for the dependent variables (mass fractions) in Concentrated Chemical Species physics. I have the mass fraction of Species A to E and one inert (total...
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