Simulation time for 2D and 3D vastly different (with comparable DoF)
Hello, I have a question regarding relative simulation time for 2D and 3D structure. I am using COMSOL RF module to simulate an optical structure. When I try a 2D case with very fine mesh density and...
View ArticleInitial Conditions for Sine-Wave or More complex disturbances
Hi Everyone, I have reviewed previous posts in Comsol forum about I.C . One of the suggested ways of applying the I.C was to do a stationary analysts before the time-dependent one. (This can be true...
View ArticleHow to integrate a table result
Hello, I have calculated surface integrals for total flux over particular features in my geometry. This outputs a table of total flux in (mol/s) vs. time points. I would like to then be able to...
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 ArticleWhat is convergence?
I'd just like to know what convergence is - in the context of COMSOL.
View ArticleDiscrepancy between particle trajectory and streamline?
Hello, I'm trying to teach myself how to use the particle tracing module, so I'm modeling a simple T-junction microfluidic channel. I get an unexpected result, however, when I trace the particles....
View ArticleUsing a derived variable as an input variable for another study
Hi, I have searched through a lot of these threads but I can't seem to find a good answer. I have applied an oscillating body load to a resonating structure (Model 1) and I am able to plot the...
View ArticleIs Cap Face feature is existed in COMSOL 4.00
Hello, I am wondering if someone still uses COMSOL 4.00 and can guid me how to block some holes in my geometry. Is Cap face is existed in COMSOL 4.00 as its in COMSOL 4.3 Many thanks Faisal
View Article160um long Gold rods - excessive reflections.
Hi guys, I'm hoping someone can help me with an issue I'm having in COMSOL. I'm trying to model a 160um by 13um long gold rod in order to get extinction spectra so I can figure out where its peak is...
View ArticlePlot a formula
Hi, I am trying to do simulation of resistivity changing versus deflection of a membrane. the membrane is subject to an input pressure from range 0 to 100[kPa]. I simulate the model parametric and...
View ArticleIn joule heating ,how to compute the resistance of a body?
In joule heating ,how to compute the resistance of a body? can you tell me the formula? such as voltage is V, the symble of current is what and the symble of resistance is what in comsol? Thanks a lot!
View ArticleTime integration in comsol 3.5a
Hi everyone, I am just wondering if there is a time integration function in comsol 3.5a. I am calculating fluid flow rate through a boundary and which is a function of time and I would like to...
View ArticleRadial diffusion
HI, I am trying to build a 1D model which is a line, but I want the diffusion to be radial instead of linear, I know that the equation is : dC/dt = D[ d2C/dr2 + (2/r) * (dC/dr )], but I do not know how...
View ArticlePhysics for a elastomeric vibration isolator.
Good morning. I'm almost finished with my model. The model consists in : 1 - Base. ( Base ) 2 - Elastomeric Rubber. ( Borracha) 3 - Lid. (Tampa) 4 - Screw Hole.( Parafuso ) The Screw Hole receive the...
View ArticleVolume at constant temperature
Dear all, I am using the heat transfer module to simulate heat flow through a rod. The rod is connected to a piece of copper that is held at a constant temperature. The problem is that Comsol only...
View Articlethe frequency domain or the transient modulator??
i want to choose the wavelength between the 300 nanometer and 1500nm. it's well known to us that the range of the wavelength correspond to a pulse with a fixed width. how can i successfully set the...
View ArticleMeshing and convergence problems
Dear Comsolians, I was finally able to draw the problem in 3D in Comsol :), am also a beginner, lol. The way I have modeled the coils is that they do not form a complete closed loop, thus I assigned...
View ArticleUncertainty in deflection of mechanical structures
I designed a silicon structure which is supposed to deflect in the transverse direction (Y axis) under axial buckling (compressive) force (applied along X axis). Even after increasing the number of...
View ArticleConstrains and laminates
Hello, id like to simulate a laminate with around 5 isotropic laminated layers. These layers are in the form of a plate with a constant area load. The model is a laminate for photovoltaics with area...
View Articleinternal wave modeling
Hello, I am trying to model a basin with two different densities to create an internal wave. I use NV and Convection-diffusion equations. Any idea how I can proceed? I have a domain and good mesh. The...
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