dynamic or static pressure?
Hi, I have a simple "problem" when using the "free and porous media flow" physics. The pressure that is calculated during the calculation is the total pressure p=p_dyn+p_stat (p_dyn=dynamic pressure...
View Articlewhat physics to use
Hi all, i am trying to implement this paper but and i dont know how to calculate the time response and phase response of the signal and how to apply this input signal. please help
View ArticleLast Time Step is not Converged.
Dear Experst I am doing time dependent FSI and i am applying sinusoidal pressure but always i am facing the same problem that is last solution time step not converged. Even Comsol is not solving the...
View Article'Java exception occurred' error
I use COMSOL 4.3a with Live link for MATLAB The version of MATLAB is 7.10.0 (R2010a) Some times, irregularly, when I run m file with COMSOL live link for MATLAB, 'java exception error' occurred. I...
View ArticleLorentz Force calculation
I want to simulate the displacement of an current-carrying wire due to an external magnetic field, due to the Lorentz Force: vect{F} = I(current) * vect{l(legth)} x vect{B}. The geometry is 3D. I'm...
View ArticleLaminar flow
Hi I am modelling the flow of liquid alloy during casting process. In the laminar flow physics, I have used inlet boundary condition as velocity field with cast inlet velocity in x-direction, outlet...
View Articlestart a study from a solution solved
simple example: i have a component loaded by a positive pressure (+1) and when is loaded i need to put under another pressure (-3) so total shoul be -2. one model,2 phisics (solid mechanic) one with...
View ArticleNorton Creep parameters
Hi I 'm simulating the creep of polycarbonate part under a constant load and constant temperature during the time. I used the Norton model, but I've got some doubts about three parameters: stress...
View ArticleLiquid Crystal - Director distribution
Hello, I would like to calculate the director distribution of liquid crystals. The formula fs=1/2(K11*(div n)^2 + K22*(n * rot n + q0)^2 +K33* |(n x rot n)|^2) describes the Oseen-Frank free energy...
View Articleelectrospray simulation
Hi, I'm trying to simulate an electrospray experiment using comsol 4.1 in order to see the formation of droplets leaving a needle to a plate. A high voltage is applied on the needle and the plate is...
View ArticleMissing Infinite Element Domain
I cannot find the Infinite element domain node, which I thought was under Definitions. I'm using the Heat Transfer in Solids in the base package. If it is not available there, where could I find it?
View ArticleCOMSOL Releases COMSOL Multiphysics version 4.3a
We at COMSOL are proud to introduce version 4.3a of COMSOL Multiphysics to the COMSOL community See: www.comsol.com/products/4.3a/ This introduces: * LiveLink™ for Excel® * LiveLink™ for Solid Edge® *...
View ArticleDielectrophoresis
Hi there. I tried to observe the particle movement effect through the "particle tracing for fluid module". However, the result of particle trajectories didn't show up any particle movement. Please...
View ArticleCutting a simple geometry in half
I'm trying to cut a relatively simple 3D geometry in half. My approach is to first partition the geometry using a work-plane and then delete the entities that I don't want. Unfortunately, some parts of...
View ArticleAccessing database
Hello, Is it possible to access the database of a study and modify the value of a dependent variable? I am running v4.3b with Matlab. In my Comsol model, I have two studies; general form PDE and...
View ArticleHow to cut a geometry
Hello, I have a 3D geometry and I need to cut half of it to create a symmetry plane. Can you please describe the steps. Thanks. Regards, Dimitris
View ArticleIdentifying Acoustic Shape of Sound Localization
New to this forum. I am a researcher but limited in acoustic knowledge. Hoping you guys can help. Is it possible to identify the shape of a sound source? We are trying to identify whether the sound...
View ArticleProblem with Mesh Swept
There is something I don't get right with the Mesh Swept option. I used the model "biased_resonator_3d_modes.mph" from the Model Library as a starting point. There they built a mesh on one face of the...
View Articlelong running time
Hey: I hope you all are well, I have a question, when I run my model it takes lots of time to run and finally the analyses wouldn't be completed. and also no errors would be appeared. Now, I am not...
View ArticleVolume concentrations in transport of diluted species module
I am confused by the fact that the" transport of diluted species node" in COMSOL only lets me work with surface concentrations. I want to model a 3D problem that has a given volume concentration as...
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