How to add a padlock in wave equation,electric?
Hi Everyone, I was exploring comsol 4.2a. faced a problem in applying it. As can be seen from my attach file, there is a small difference between the two Wave Equations.There is a padlock in the second...
View ArticleProblem with multiple domains in solving PDEs
I have imported a complex 3D-structure from SolidWorks which I want to solve the Laplace equation to obtain the electric fields. I have, rather tideously, defined all the boundary conditions and drawn...
View ArticleFace mesh does not respect face vertices
So I am trying to create a boundary layer mesh for a fluid flow model. I keep getting the following error Face mesh does not respect face vertices. What does this mean?
View Articlefinding fringe capacitance
hello sir i am new in comsol. i am trying to find capacitance of a device ..when voltage of drain=voltage of source=0 volt and gate =6 volt. but i don't know how to put boundary conditions on the...
View ArticlePlotting unwrapped phase
I am plotting the phase response of a loudspeaker, and I want to unwrap it (like what the Matlab command unwrap() does)www.mathworks.com/help/techdoc/ref/unwrap.html Any ideas?
View ArticleIntegration of a value over cross-section
Hello everyone, I have a model of molecular diffusion in a cylinder (axisymmetric geometry), and after solving (stationary solver) I get the concentration field c(r,z). I would like to get rid of the r...
View Articleconversion from 2D to 3D
hello, I am building a 'comb drive' model, in the 'electrostatics' division of the 'AC/DC module' in COMSOL 4.2. I need to 'extrude' a 2D model into a 3D one. How do i do that? Thank you
View Articlecluster computing mpi
Hello, I am trying to run my models from comsol on our University's super computer, and having difficulty with the $PBS_NODEFILE command. Can the PBS_NODEFILE also be used to run generic MPI programs?...
View ArticleGeneric 3D color/contour plot of parametric sweep values
Hi, I do a parametric sweep and sweep two variables (say, width=1,2,3; height=4,5,6). I select the dropdown box that says "All combinations" so that I get all combinations - i.e. width=1 and height=4...
View ArticleHow to define the zero potential at infinity boundary in electrostatisc of...
Hi, all I am not very familiar with COMSOL, just begin to learn, Looking forward to your help to address the issue "How to define the zero potential at infinity boundary in electrostatisc of ADDC...
View Articleacoustics
Dear sir, i am using acoustics equations are writing in Matlab. i need some help from you. In same equation are introduce in comsol and also avilable for matlab programs are introduce in comsol. give...
View ArticleHeat exchange during ice cube formation !
Hi, I'm trying to solve a heat exchange problem coupled to a phase change in 2D. The model consists in a small volume of water on contact with a metal plate. I cool down the plate gradually so at some...
View ArticleImplementing non-standard boundary condition
I am trying to solve a standard diffusion pde in potential form. The resulting equation consists of a term with a first-order time deriviation and another term with a second-order space deriviation....
View Articleimpose heat flux fluid/fluid Interfaces: laminar (tpf) and heat transfer in...
All, I would like to impose a heat flux on a 2D fluid/fluid interface. I have considered utilizing an equivalent volumetric generation using the delta function and even the tpf.Vfi function to turn on...
View Articlegot problem with my simulation on nano scale particles
I would like to simulate the magnetic force on an iron particle due to an external magnetic field. The magnetic field is generated by a wire, conducted with steady current. The wire is about 30um in...
View ArticleDependent variable definition
Dear all, I am having trouble finding which variables the solver is solving for. I know that I can see all the variables if I activate the equation view. However, out of all these I am not sure which...
View Articleimpact
how can i solve a structural mechanics problem where there is a contact between to structures with certain velocity?
View Articleabout parametric sweep and optimization
I built a reaction model, I want to know the equilibrium states of the reaction at difference concentration of one material. so I use the parametric sweep to calculate the equilibrium results. but when...
View Articlematlab function unwrap giving odd results?
Dear all, I am trying to unwrap a phase plot, using the unwrap Matlab function. This function works fine in Matlab on the same data but gives erroneous results in Comsol. I added the function in the...
View ArticleInfinite elements problem in AC/DC modul
Hi all, I have problem concerning of "Infinite Elements" in AC/DC modul. I know there are couple of discussion about this but this is still unclear to me. I have read the manual and I followed the...
View Article