Unsteady Analysis
Hi, I am solving a unsteady state problem, in which i need to solve two unsteady equations. The solution of first unsteady state equation, which depends on time, is used in solving the second unsteady...
View Articleparticle tracing
Hello everyone, I have a problem with the particle tracing module: I want to evaluate mixing performance of a mixer. how I can define four part at rotating machinery and then define unique particle...
View Articlemodeling electric current
Hi I need to obtain the electric current density field in a medium attributed to a pair of source and sink electrodes with known current. what physic should I choose and what boundary conditions...
View Articleelectric currents model
Hallo, i have a question about the electric currents model. My simulation is 2D axisymmetric in frequency domain. The geometry is a solenoid which has two turns. As you know, if the current flows...
View ArticleHow to realize moving boundary integration in COMSOL?
This is a math problem in calculating the photo-ionization of streamer discharge by comsol. The 1-d calculation domain is (0,d), and one point inside this domain is x. We need do the calculation in two...
View ArticleTest function of Electric field
Hey All I am working in the 2D Piezoelectric module and want to take weak form of the electric field in X and Y directions. I used test(pzd.EX) and test(pzd.EY) but I am having problem in it. I think...
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 Articlehow do I know if my license has live link to matlab
Would you please check my license and see if i have
View ArticleBaw Resonator Problem
Hi I am working on a baw resonator. For our simulation we have considered a 3.5a COMSOL 2D model of Thin Film Bulk Acoustic Wave Resonator in the model archives of COMSOL. So we treid to simulate the...
View ArticleTrouble coupling heat transfer physics for both fluids and solids
Hey all, So I'm getting stuck with my model where I try to couple three different physics. The three physics are: Electric Currents, Heat transfer in Solids, and Heat transfer in Fluids. Basically what...
View ArticleMultiple input ports in RF problems
Hello, I'am doing a simulation with RF module. It's about the mode analysis of a rectangular silicon waveguide. There are two waveguides. To propagate the monochromatic light of 1550nm (1.935e14 Hz ),...
View ArticleError to initialize a physics interface created with Physics Builder in...
Hi all, I am trying to compile with LiveLink for Matlab (Matlab version MATLAB_R2012a) a Comsol model (Comsol version COMSOL 4.3.0.151) that uses a physics interface which I created with the Physics...
View ArticleSpatially-varying boundary condition (electric potential)
Hi all! I am using the Electrostatics package and need to define a surface with a linearly-varying electric potential that depends on one dimension of the model (e.g. V(x,y) = Kx). I tried to define a...
View Articleheat generation calculation
Hi, I am modelling microwave heating by Comsol 4.2 I used heat source domain and electromagnetic power loss density as heat source but I couldn't calculate heat generation terms (W/m^3) When I use...
View ArticleRectangular Pulse Train Creation
Hello, I am attempting to create a pulse train for my model. I am new to introducing pulses and would like an equation to place on my electrcial potential module to create the following: Rectangular...
View ArticleSurface tension as a variable
Hello all, I have a general question about surface tension in COMSOL. Can surface tension be assigned as a dependent variable? More importantly, can it vary in time AND space? Or be assigned as a...
View ArticleAC/DC Module Boundary Condition
I am currently working on a project to model a section view of a human forearm. The model terminates just before the elbow and the boundary condition there is a problem for me. I currently have the...
View ArticleVector operator expansion ∇·(c∇u) in 3D
hi I am working on a set of coupled differential equations in the equation based modeling (3D). Assuming that u=[u, v, w]. I am looking to evaluate the term ∇·(c∇u) to obtin the matrix c. I was...
View ArticleWeak form of Electric field , test(pzd.EX)
Hey all I am working in the 2D piezoelectric module and I want to take weak forms of Electric field in different direction, test(pzd.EX) and test(pzd.EY) but its showing error. When I try by making the...
View Articlestudy the effect of voltage on piezoelectric microgripper
hi,i want to perform the pressure and strain analysis (by varying) on the microgripper model given in comsol 4.2.please help
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