Interpretation of results
Hi, what is the difference between "Line Integration", "Line Maximum/Minimum" and "Line Average" under subnode "Derived Values"? What is calculated specifically? How to interpret the results? For...
View Articleparametrize the position of a point in the geometry gives an error message
Dear Comsolfriends, I want to do a parameter study for the size of my geometry, but I get the following error when trying to set the position of a POINT using a parameter defined before in MATLAB...
View Articlesave the mesh points into a text file
How can I save the mesh points into a text file or some similar? Thanks!
View ArticleIssue importing ipt files from Inventor with the CAD module
Hi, I can't seem to import a simple IPT cad file (that has a helix built in) from inventor, the import module gives me an error back saying: Not a valid ENTITY type for this operation - Detail:...
View ArticleScattering boundary conditons for non-normal incident
Hi all, I'm wondering, if it possible to use the scattering boundary conditions in the RF module to make a boundary transparent for a plane wave with a known wave-vector (which is different from the...
View Article"Undefined value found" Error when simulating EM-Wave on imported 3D Pyramid
Hey all, I am trying to simulate the E-Field enhancements on a micro-pyramid structure for which I imported a pyramid with rounded corners from AutoCAD as a .sat file. I set up everything the way I...
View ArticlePML does not work during wavelength sweep
I was simulating the scattering from a nanodisk by normal incidence. With a spherical PML, the scattering field should be basically symmetric below and above the disk plane. It is indeed so when I...
View ArticleStore solution and use as a boundary condition for the next run
Hi Does anybody knows how to apply the results obtained at the outlet of first run back to the inlet as an inlet bounrady condition? Actually the objective is to study a flow in a long clyinder by...
View ArticleProblem related to imported mesh file
I was trying to import a mesh flle (mphtxt) file from Simpleware Scan FE software. However when I import this mesh file in COMSOL and throw all the physics on it, following error appear : Can you...
View ArticleFuel tank simulation
Hi, I have a project about fuel tank simulation. The thing that I try is similar to the sloshing tank example. However, since the fuel tanks are closed [ :) ] I need to limit the deforming mesh. Has...
View Articlespecifying varing coefficient - interpolation function
Hi all, I would like to specify varing htc via interpolation function and apply it to a heat flux boundary condition. I am attaching a sample file. - Model: 2D-axisymetric (i.e.cylinder, mm), heat...
View ArticleHow to use user defined functions as physics's input? Thanks!
Hello, every one! I am learnging to use COMSOL4.2 and want to add AC signal as my device's input. Just as Eric told me to write an equation as the input....
View ArticleImporting a file from AutoCAD to COMSOL
I have created a 3D building model on AutoCAD and wish to import it to COMSOL for CFD analysis. Can I know the process for importing?
View ArticleVelocity of solution
Hi, Since it depends what speed calculations? I created two identical geometry. One in 2D it is counted in minutes. Second in 3D it is counted for 30 minutes to 1 hour. It is possible to calculate the...
View ArticleAbsolute pressure sensor
I'm working on simulation of absolute pressure sensor. I want to know that when i compute the result for stress it shows the total stress. I want the longitudinal and transverse both stress at...
View Articleelectrostatic force cause displacement in parallel plate capacitor in COMSOL
Hi, I have been designed a parallel-plate capacitor in COMSOL. Where one plate is connect to voltage of 10V and other one is connected to GND. and a air box is around the parallel plate capacitor. As I...
View ArticleUndefined value found in the stiffness matrix, requested mesh quality cannot...
Dear All, I am simulating a sphere flowing in a microchannel with solid traps (2D for simplification). Automatic re-meshing is activated. Two scenarios are considered: Scenario 1, the sphere will...
View ArticleDifference between two modules in comsol
What is the difference between module " Structural mechanics--->Poroelasticity(poro)" and module "Fluid flow---->Porous Media and Surface Flow"? Anybody knows? I was gonna implement solid liquid...
View ArticleSome questions about one example in model library
I am redoing the example of "Terzaghi Compaction", and I have some questions or confusions: 1) In the "Darcy's law----> storage model" section after part "Definition", we just need to set K as K_s,...
View ArticleWhat physic need for SQUEEZED-FILM DAMPING MODELS FOR MEMS in COMSOL
Hi all, I am working on SQUEEZED-FILM DAMPING MODELS FOR MEMS in COMSOL. Where one of the plate(1) is fixed and other plate(2) is movable when applying pressure. Whole structure should be inside the...
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