contact modeling problem
Hi everyone I ve been working on a contact problem in which there are 2 concentric cylinders . the cylinders are not in contact initially but the inner cylinder expands and comes in contact with the...
View ArticlePoisson Nernst Planck and Navier Stokes equation
Hi everyone, I am trying to simulate the electro-osmotic flow in a nano-channel using the Poisson-Nernst-Planck and Navier-Stokes equations coupling them from the Electrostatics,Transport of dilute...
View ArticleReflection/transmission spectra of a free standing Ag film with periodic hole...
Hi, I want to use COMSOL 4.3a to simulate the reflection and transmission spectra of a free standing Ag film with periodic hole arrays. There is an error " Failed to find a solution for the initial...
View ArticleSubsurface flow in heterogeneous reservoir......
Hello all, I am trying to simulate a model which contains square geometry and two circles(inlet and outlet). I am a new user of COMSOL and facing many problems like how to put inflow and outflow rate...
View ArticleUsing simulated potential to simulate magnetic field.
I have a simple 5 domain model, composed of roughly concentric spheres. I am modeling a transmembrane potential on the 3rd domain using the General Form PDE physics. This part is working correctly. I...
View ArticleCoupling Poisson and Transport
Hi, I am using Comsol 4.3a and want to couple Poisson and transport for determining the flow of charge (or electrical current) within an wire due to application of voltage across it. Now, the output...
View ArticleTime dependant Structural Mechanics & Magnetic Field
Hy Can anyone please let me know that is it possible to simulate time dependant magnetic field when force or some external conditions are there in which geometrical position of the shape is changing....
View ArticleParametric sweep : Can I bypass (ignore)the error occuring for a particular...
In coupled MEMS electrostatic study, I defined two parameters: Vdc and InitialGap. These two parameters were used for parametric sweep on the electromechanics module of Comsol 4.3. Now Comsol runs my...
View ArticleHow can simulate this impulse function : 50 Kilovolt ,40/80 microsecond ?
I select AC/DC electrostatic then time dependent, i have two electrodes and insulator between them which need to apply impulse wave on the upper electrode and the other electrode connected to ground....
View Articleheat transfer in fluids time dependent error
Hi My problem combines laminar flow and heat transfer in fluids. It runs OK in stationary mode. It runs OK also in either time dependent flow or heat transfer . If I try heat transfer+flow in time...
View ArticleRotating geometry in 3D plot
Dear all, First, I design a rotating disc simulation in 3D space. I select the model physics by 'Solid mechanics'. In this physics, I insert some values to 'Velocity field' of 'initial Values'. x =...
View Articleerror in time dependent boundary condition
Hi I usually define a function e.g. rm1 ( ramp function) and defining the boundary condition as rm1(t). This usually worked fine but now suddenly the function is orange colored and it says "unexpected...
View ArticleTo find mutual inductance and coupling coefficient
Dear all I modelled a 3D spiral coil with two turns, of two different coil separated by distance. I applied the current density for the coils. I want to evaluate self inductance and mutual inductance...
View ArticleChanging view of matlab function mphplot
Dear all, I want to plot my COMSOL model in a Matlab figure using the mphplot function. However the orientation of the model in the plot is the standard orientation of the Model in COMSOL. Is there any...
View ArticleModelling magnetic field for capacitor.
Hi, I am working on the project of the capacitor. Recently I have succesfully simulated electric field but now I would like to simulate magnetic field and I unfortunatelly have no idea how to make it....
View ArticleBoundary conditions in heat transfer
Hi, I want to model a muscle tissue containing a capillary blood vessel. Now I’m using a simple model for start… My model geometry is in the attached file. As I want to model heat convection between...
View ArticleScatterer on substrate, RF module
Dear All, Probably some of you RF module users saw module “Scatterer on substrate” in model gallery. I have question about that, and I have question about total field formalism in generally. So, basic...
View ArticlePartial differential terms in Monopole source term
Hi, I am trying to solve an acoustic problem, in which the monopole source term contains the partial differential terms. I tried using d(p,z), but I would like to know if d(p,z) accounts for total...
View ArticleScatterer on substrate not converging for smaller wavelengths
Hello, Can anyone help me regarding the scatterer on a substrate? I am trying to simulate the exact same model with no changes but at 200nm incident wave. It simply does not converge. Does anyone have...
View ArticleFluid flow - solid body rotation coupling problem
Dear all, I am working on a 2D model of a turbine subjected to air and to do this I guess I need to use laminar flow and ale. Also solid mechanics to define a free to rotate connection. What I want to...
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