Switch the boundary condition from flux to pressure head (Richards’Equation)
I read some paper, in the old version of COMSOL, we can choose a Mixed boundary condition (mix of Dirichlet, Newman and Cauchy conditions). in order to automatically transfer the boundary condition...
View ArticleSwitch the boundary condition from flux to pressure head (Richards’Equation)
I read some paper, in the old version of COMSOL, we can choose a Mixed boundary condition (mix of Dirichlet, Newman and Cauchy conditions). in order to automatically transfer the boundary condition...
View ArticleMagnetic Field Simulation
Hi, i'm currently trying to do a mf analysis of the system in append figure. The four quadrangular structures are coils with a external current applied. I defined all the domain's material and added...
View ArticleDefine a function like Linear elastic-perfectly plastic behavior.
How can I define a load which increase linearly up to time t0 and then stay fix by time. I defined something like "F*(rm1(t<t0)+step1(t))" which step function location is time t0. the only section...
View ArticleRecreating Jet Flow in COMSOL
I have temporal and spatial velocity profiles that I would like to try and recreate in COMSOL. At 0mm from the nozzle (d = 2.4 mm) the velocity is 110 m/s and at 12 mm the velocity is about 100 m/s. It...
View ArticleMatlab functions in Comsol - limited compared to 3.5?
Dear All, I'm running Comsol 4.1 via the LifeLink from Matlab. Basically it works fine but I encountered a limitation, which was not present in the version 3.5. I have a Matlab function which sets up...
View ArticleError-Automatic remeshing
Hi, I encountered a problem about "Automatic remeshing" with "deformed geomerty" and Time-Dependent Solver When I ran the program, Comsol always displayed a Error: Unsupported operation on this type of...
View ArticleTime to Reach Steady State in a Diffusion Problem
Hello, Is someone able to help me, please? I'm using COMSOL to model a diffusion problem. I have solved it using the stationary solver. I am able to see that at steady state the concentration on the...
View ArticlePML Scaling factor in COMSOL 4.3
Hi, I am doing a 3D simulation with COMSOL 4.3 to find the field distribution and the mode of a waveguide where all the cladding, the core and the substrate have different refractive index. I have...
View Articlesurface to surface radiation without surface
Hello, I work on a molten charge and i have some issues with radiation. Usually i use a surface to ambient radiation condition but it is not enough precise for my problem, i have to take into account...
View ArticleComsol RF module norm and phase
Dear all, I have a problem with Comsol, a very naive one. I am trying to do a harmonic simulation (a single frequency in frequency domain model) of the EM scattering in a domain. For example if I have...
View Articleco-efficient of thermal expansion
Hello evrybody, Can anyone help me to know if I can input my co-efficient of thermal expansion as a function of Stress and Temperature or not. And if possible how to do that. Thank you.
View ArticleOutput pressure of the transducer adding Vac + Vdc
hello, I 'm working on a capacitive transducer, using the electromechanics(emi) model. Now I want to observe the output pressure of the transducer in the frequency domain and I add a voltage V=Vac+50...
View Articleerror in statonary analysis of a biased resonator
Dear comsol community, I'm working on comsol4.2a , I would be glad if i can get a solution for my following two queries: 1) I have gone through the modelling instructions given in the 'Stationary...
View Articleplot
Hi I simulate the mode profile of the rib waveguide. Now i want to plot the normalised intensity(arb unit) in the x and y directions. Do you know how can i do this?what is the arb unit? how can i find...
View ArticleResonance frequency of beam (calculation+plot)
HI I want to calculate and plot resonance frequency of cantilever that I designed in MEMS module. Based on the previous discussions here I understand that I should do the study in "Eigenfrequency" and...
View ArticleNeed Help with Simulating Thermal Stresses in a Layered Plate
Hi Experts, I kept running into this message: Failed to find a solution. System matrix is zero. Returned solution is not converged. I wasn't sure what exactly went wrong in my model. I'd really...
View ArticleAbsorbing boundary condition for transient wave propagation problem
Hi! I am wondering if I can define an absorbing boundary condition for a transient ultrasonic wave propagation problem (let's say in a 2D plane strain transient module). The option certainly doesn't...
View Article2D geometry but illuminated from below
Hi, I want to create a 2D geometry but illuminate it from below, or out of plane, with a plane wave. Whenever I try and set the Background Field as exp(-i*emw.k0*z) (in x direction) I get errors as it...
View ArticleComsoe error when useing with MATLAB
I have an error that continually comes up when useing MATLAB and trying to have the program access comsol. I get one of two errors the first is Feature Compile Equations: Time Dependant (so11/st1)...
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