Stress gradient of anisotropic material
Hi, I am using the anisotropic Silicon material parameters and was wondering how to apply a stress gradient to this. I've tried some equations manually and I'm not getting the same results from my...
View ArticleConstraint for variable in PDE- Mode
Hi everyone, I'm trying to simulate fractures by using a phase field model. The variables u and v describe the displacement of the body and s is the phase field variable that describes wheter the...
View ArticleMesh Problem
Hello, I have problem with mesh generation for my model. I made a 3D glass beads with lots of grains. When I want to mesh that I faced some error in meshing. sometimes it meshed but then during study...
View ArticleCapacitance from sinusoid voltage
Hi everyone! For modeling I am using 3D Comsol Multiphysics // AC/DC module // Quasi Statics, electric // time harmonic analysis. In postprocessing Comsol calculates and plots electric potential and...
View ArticleDefining the applied voltage V as a function of time
Hi, I am Naveen doing my MS project "modeling of electrosorption" at Hindustan Unilever R&D,bangalore.In my problem i want to define V=0 at time t=0s and V=V0 at time t>0.Here +V0 is the applied...
View ArticleNonlinear solver scheme
Dear Ivar, We are solving a nonlinear transient problem using a "fully coupled approach" with the constant Newton option (damping factor =1). The termination criterion is the default tolerance with a...
View ArticleUse a solution of a very similar problem as initial values...
Dear all, I am generating a phononic band diagram of a photonic crystal (mechanics-analogy to photonic bands...) by sweeping the bloch-floquet k vector from Matlab (i.e. a boundary condition - but in...
View ArticleWhat's the difference between the "harmonic propagation" and "scattered...
Dear all: IN the RF => In plane wave model ,What's the difference between the "harmonic propagation" and "scattered harmonic propagation"? Q2. if I set the square and draw the rectangle around the...
View ArticleUndefined value found in the equation residual vector.
I am trying to model a pem fuel cell. Although I have entered all parameters and values, i have some errors as follows; Undefined value found. - Detail: Undefined value found in the equation residual...
View ArticleHow to Couple Free and Porous Media Flow with Heat Transfer In Solids
Hi Everyone, I am new to COMSOL and I am trying to simulate a solar panel cooling system. I am trying to simulate in 2D the heat transfer between a thin rectangular layer (the photovoltaic cell),...
View ArticleError - 3D LID Driven Cavity Flow
Hello Forum, i try a computation for the "3D lid-driven cavity flow" model. I got a Comsol Error: Failed to find a solution. Divergence of the linear iterations. Returned solution is not converged. I...
View Article2 Separate Stranded Coils in Multi-Turn Coil Domain
Hi all, I have 2 separate stranded coils to be modeled for transient behavior (Current Pulse input). Since these coils are not of regular shape (linear or Circular), i had to go with numeric coil type...
View ArticleUsing the grad-free optimization and the with operator.
Hello, I am currently using the Grad-free operator to try to solve an inversion problem. The problem consists of taking measurements of a magnetic field at the surface. We are making synthetic models...
View ArticleCUDA and COMSOL
Dear all, I have a new NVIDIA Quadro GPU and I would like to use it to accelerate my simulations, is it possible to use it somehow? I looked for some informations and it seems to me that CUDA it's...
View Articlecomsol error failed to evaluate variable
Hi, i am trying to design spiral inductor using the physics "magnetic and electricfield(mef) but i have this error Failed to evaluate variable - Variable : mf.normB - Geometry: 1 - Domain: 2 3 4 5 6...
View ArticleProblem of using femtime() in COMSOL 3.5a
Hello all, I use femtime() in matlab to solve a dynamic FE problem as follow: fem.sol = femtime(fem,'Tlist',tspan); where tspan is an equally distributed time list. tspan = [t0,t1,t2,...tn]. Now, I am...
View Articledefine mixed boundary condition?
Hi to all, How can i define a mixed boundary condition? I can not find a way to write an equation like du/dx = (alpha/beta)*u alpha & beta are constant. Tanx.
View ArticleStress gradient of anisotropic material
Hi, I am using the anisotropic Silicon material parameters and was wondering how to apply a stress gradient to this. I've tried some equations manually and I'm not getting the same results from my...
View ArticleConstraint for variable in PDE- Mode
Hi everyone, I'm trying to simulate fractures by using a phase field model. The variables u and v describe the displacement of the body and s is the phase field variable that describes wheter the...
View ArticleMesh Problem
Hello, I have problem with mesh generation for my model. I made a 3D glass beads with lots of grains. When I want to mesh that I faced some error in meshing. sometimes it meshed but then during study...
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