Mixing two different fluids in fluid flow
Hi I have been working on a flow analyzer that has two inlet and an outlet. I have two fluids, one is very dense and the other is a very dilute substance, both of them are completely different and they...
View Articleheat transfer simulation
Hi, I am trying to simulate heat transfer of a 3D closed box with a fluid(Nitrogen) inside it and some solid electronic components that are heat sources. Actually I am a little confused with different...
View ArticlePML in 3D RF module COMSOL 3.5a
Dear all, I have a question about PML in 3D RF module. Attached model is to simulate a plane wave propagating in air along z direction. As you can see, there is a huge distortion between the fields in...
View ArticleFluid-Porous Slip boundary conditon
Hello, I focus now on the flow and solute transportation simulation in the free flow and porous media. There are traditionally one singe formulation, typically Brinkman and two-domain coupling with...
View ArticleFailed to call interpolation function in material
Hi everyone, I want to insert a function in a material. Function is frequency and relative permittivity relationship. I make function from a text file and then call the function by typing the function...
View ArticleHeat Source and Heat flux
I am simulating laser heating of material with gaussian pulse beam. I have doubt with heat source and heat flux? shall I use both or just heat source for my modeling? Any help will be highly...
View ArticleLevel Set Method: Unable to Re-compute
Hello, I'm using two-phase flow, level set to simulate mixing of two fluids (gases) and got my model to run (is not correct in current state but did run), however, when I make a small change, I cannot...
View ArticleSame BC for 2Axis Symmetric and 3D, yet different Delta_P
Please Delete, I made a silly geometry error!! UGH!
View ArticleFlux Calculation
Hi all, I am doing simulation for a problem that involves coupling between electrostatics and transport of diluted species. In the problem I used "No Flux" condition for all species at one wall. I was...
View ArticleExport 3D simulation data to reuse it in a 2D simulation
Hi, I simulated the laminar flow in a tube-like structure in 3D. Then I want to use the transport of diluted species in the centerline cut plane. I recreated the 2D centerline cut plane geometry in a...
View Articlepoint source in RF model
Hello, I met with a problem that when I add a point source, for example,electric dipole or magnetic dipole, in 2d structure, the point source can only excited in a limited small range, although the...
View ArticleHow to consider groundwater table in soil
Hi I am a beginner of COMSOL, I am trying to use COMSOL to model soil behaviour. As you know the soil always water in it, which make a difference of stress state, can be total stress and effective...
View Articledefine frequency value in global definitions -> variables
Hi, I need to use electric current interface and frequency domain study. I want to give applied input voltage in terminal 1 as Vo=V0*sin(2*pi*f*t) So in the Global definitions -> variables I set...
View ArticleGenearal question: Mesh density
Hi all, I have a general question, whether the high mesh density will give a good convergence, or not ? As i simulate a nano-particle optical scattering, i found that use a smaller mesh, the resonance...
View Articleintegration points
Hi I need to extract the value of a parameter with in an element. I studied in one of the forum that I can do that by using gauss integration points while exporting the data. But How and where I can...
View ArticleCustomizing node numbering of elements
Hi Everyone Is it possible to customize how Comsol assign node-numbers to the mesh nodes? For example if we consider a 4 node quad element, Comsol starts at the lower left corner as node 1, and then...
View ArticleWhat would be your ideal COMSOL workstation?
Hello all, I am in the process of building my own COMSOL workstation, and am looking for advice. If you were building your own computer from scratch, what parts would you be sure to get (besides a...
View ArticleJoules heating in a Primary terminal of Current Transformer.
Hello.. I am trying to model a Primary terminal of A Current Transformer. The terminal is to carry a current of 300 Amps. I am stuck with how to inject the current into the system, so that I get the...
View ArticleHigh RAM use with few degrees of freedom
Hi everybody, the 3D model attached has a swept mesh with 3468 hexahedral elements and the solver solves for 31395 degrees of freedom; while solving, the request for RAM "explodes" and becomes larger...
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