Steam
I'm working with steam and condensate phase shift. I wonder who can help me with the correct handling of steam?
View ArticleHelp. contact pair penetrate each other.
Dear, all, I have a basic question regarding to mechanical contact. I have just run a very simple simulation: a deflected beam contact a fix cubic. However, I always got penetrated displacement of the...
View ArticlePoisson-continuity coupled equation
Hello, I try to model the corona discharge in wire-cylinder geometry governed by the equations: nabla (V) =- rho/epsilon0 (Poisson equation) and grad (rho) * grad (V) = rho ^ 2/epsilon0 (equation of...
View ArticleMixing two materials
I'm trying to simulate the behavior of a model made of a material which is a mixture of two materials available in the library. The materials are mixed in unequal proportions. I'm able to calculate the...
View ArticleStep function
Very simple question, but I can't find out how to do it. I have a external temperature, "Temperature 1", which is 100 C. After 330 seconds I would like it to drop 80 degrees to 20 degrees. I should be...
View Articlehow to model random " conductivity" variation?
Hi, I am doing an AC/DC study of spreading resistance. for example, I have a fixed shape block of Semiconductor (poly-Si) which is made of small grains(polycrystalline ). these small grains has slight...
View ArticleT amb in surface to surface radiation module
HI ! I just had a doubt in the following model,www.comsol.com/showroom/documentation/model/494/ why is T amb for "surface to surface radiation" boundary has different values ... ? even though for an...
View ArticleFail to evaluate the derivative at a line
Hi, I am using COMSOL 4.0 RF to model light scattering. In 2D model, i calculate a very thin sheet scattering, which is 1D geometry in such 2D model. So i use the surface current boundary condition for...
View Articlemodeling evanescent wave
Hi all, How to generate or simulate evanescent wave in COMSOL? can total internal reflection work? There seems to be rare examples in this field and expect for any ideas from you.
View ArticleModeling a Diode
Hi, I am trying to follow the example of semiconductor diode available in:www.comsol.com/showroom/documentation/model/114/ in a COMSOL 4.2. I believe that I have followed exactly what is describe in...
View ArticleLocal Edge System
Hello, I'm trying to implement a "Predescribed Displacement" Condition on an Edge using the local Edge Coordinate system. But i have the Problem that i couldn't find a reference to the "Local Edge...
View ArticleCan I use COMSOL to solve integral equations?
Dear all, I have some integral equation to solve. Can I do that with COMSOL or I always need to change it to PDE? Thanks a lot!
View ArticleCapillary filling changing area
Dear all, I have been working on a simple 2-phase flow through a capillary. The next step in my model is for the fluid (water) to leave the capillary to a duct with a higher surface area. The model...
View ArticleQuestion on objective function for 'horn_shape_optimization' for own design
So I understand the objective function is: -10*log10(0.5*realdot(pm,pm)/2e-5^2) which makes sense when reading literature but when looking at the definition of 'pm':...
View ArticleEnforcing variables to be greater than or equal to zero
Hello, I'm modelling diffusion through a porous medium with adsorption. The main dependent variable for mass concentration tends to go below zero which is not true in reality. Is there a way to enforce...
View ArticleHelp me please! how to draw the magnetic field lines in 3D, as
Hi all! I need to add the magnetic field lines (and possibly add metal bars between the head and emitter) to the model 2190 Absorbed Radiation (SAR) in the Human Brain. PS Since I'm a beginner, then I...
View ArticleTemperature mapping with Model Coupling
I wish to generate temperatures in a model and subsequently map the temperatures them to a similar model in a different study. The two models will have the same geometry. However, the model will be...
View Articlehow to couple two time dependent physics equation?
in a time step the result from the first equation is use to the second equation ? and then the next step the result of second equation is used to the first equation. for example :...
View ArticleMeshing of multilayered Hemispherical 3-D geometry and Time dependant heat...
Hello Sir, I am trying to simulate a 3D tissue model, which is hemispherical in shape. I am imposing a sinusoidal heat flux on the top curved surface of hemisphere. After solving the transient bio heat...
View Articlemodeling sessile droplet evaporation
Dear Firends, does any one has experience with modeling phase change from liquid to gas ? is there exists any tutorial ? I intended to model evaporation of single droplet pinned of relatively hot...
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