Problems with using deriviative opertaor (4.3.0.151)
I'm using the general PDE module coupled with creeping flow. The PDE solves the electrostatics problem (Laplace equation) and finds the electric potential (phi) everywhere. I'm trying to put in a slip...
View ArticleMutual inductance for 2 coils seperated by a distance
HI, i have done applying ac current-time dependent analysis in a coil and analysed the magnetic flux density with the theortical equation of biot savart law for circular coil. Now i have to calculate...
View Articlescattering of a sphere and compared to analytical solution
Hi everyone I was trying to work on the model which appears in the Model Gallery "Acoustic Scattering Off an Ellipsoid Model ID: 12417" to describe the scattering of a solid sphere, but I got some...
View ArticleCoils for cooktop
Hello, I am in the process of optimization of an inductor Cooktop (magnetic field distribution and proximity effect (for losses)). However, I would like to know the method to be able to correctly...
View ArticleInviscid Flow
Hi, I want to model a 2d inviscid flow in comsol v4.1, but when I set Dynamic viscosity=0 , I have some convergence problem. It can be solved by using full Navier-Stokes Equations, but when I set the...
View ArticleCOMSOL Error for Initial Values(RF Module)
I am defining a model with different concentrations of oil and water and trying to measure the heat distribution by using the microwaves. But I obtained the error mentioning Initial values: THE...
View ArticleCOMSOL Releases COMSOL Multiphysics version 4.3a
We at COMSOL are proud to introduce version 4.3a of COMSOL Multiphysics to the COMSOL community See: www.comsol.com/products/4.3a/ This introduces: * LiveLink™ for Excel® * LiveLink™ for Solid Edge® *...
View ArticleA Fabry-Perot Resonator simulation
It's a 3D simulation, there are two Bragg mirrors on each side of the cavity, the geometry is in the attach file[3d geometry].[ Bragg mirror is just alternative silicon and air with thickness of λ/4n...
View Articlemodeling of turbulent flow in pipe and annulus. (pipe has porous wall)
Hi, I am trying to model turbulent flow in a pipe and annulus and find the pressure and velocity distributions. The flow is going to the pipe and is coming back from the annulus. The pipe has porous...
View ArticleOscillations of E/H inside a sphere bounded with a PML
Hello, I have some results but I'm not confident if they are correct. I am simulating an antenna which should generate very strong electric field, and I want to test it at the frequency of 200MHz...
View ArticleModel BH-curves with remanent flux density at H=0
Hello, I make some studies to determine the magnetic properties of metals and have to take in account a small remanent magntic flux density B. I defined a sample material with a known BH-curve and at...
View ArticleSpiral Coil
Hi, I am trying to simulate a spiral flat coil. The input is the current I define while I would like to see the magnetic flux density generated. I made three models in the same way, but the dimensions...
View ArticleProblems with mesh definition
Hi, I want to know if it is normal results change with the size of the mesh? I am using RF module, and implemented one of Comsol examples the Branch-line Coupler, when I change the size of the mesh...
View Article"Failed to evaluate variable" Error
Hello, I am new to comsol and am trying to design and simulate a square diaphragm piezoresistor pressure sensor. Attached is my model. I am able to mesh my model but I keep getting "failed to evaluate...
View ArticleNo species released when using Transport of Species model
Hi, I am trying to add some tracer to the bulk flow. In Study 1, I am running a Steady air flow, and then in Study 2, I add a tracer to the flow. The tracer is released from a point (a source using...
View ArticlePixel hunting to select object in Comsol 4.4
The new version Comsol now uses mouse hover to high light object and click to add in some of the CAD tool. However many times the hightlighting is very tricky and I have to pixel hunting near boundary...
View ArticleTo demonstrate a "sieve" at the particle tracing module
Hi all, now I'm trying to demonstrate a particle sieve using the particle tracing module. I expected that the particles bigger than the pore size of the sieve could be filtered and stuck on the sieve...
View ArticleSurface acoustic wafe sensors - Out put voltage
Hi Is want to simulate a Surface Acoustic Waves (SAW) device. For reducing the problem complexity, I work in 2D in the plane cut indicated in the figure here below (top view of metal lines). A floating...
View ArticleConnection between NIST REFPROP and comsol
I am using comsol 4.2a vesrion for modelling hydrogen storage. Can I connect NISTREFPROP to comesol like matlab?
View ArticleFrequency domain modal analysis of a cantilevered beam
Hello all, I am trying to run frequency domain modal analysis of a cantilevered beam. I have built the model in Comsol 4.1 and have assigned desired material properties. Have applied fixed constraint...
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