How 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 ArticleWhat is convergence?
I'd just like to know what convergence is - in the context of COMSOL.
View ArticleTemperature effect in Electrostatic module.
Hi, I am using Comsol ver 3.5a. Can anyone guide me that how could i observe the effect of temperature on capacitance value in Electrostatic module ? From where i can change/control the temperature in...
View ArticleElectric field not adjusting with moving mesh
Hi, I have created a model which is effectively a capacitor with a moving plate. I have ground electrodes on the fixed top plate and +/-100V electrodes on the bottom moving plate. I am using ALE with...
View Articlefailed to generate mesh for face
hello, i imported a solid geometry to comsol, but when i generate mesh i get error: failed to generate mesh for face, i tried to make custom mesh for these faces, but did not solve the problem. can...
View ArticleDiaphragm
Hi, I am trying to do simulation of air horn diaphragm, Inputs: Diaphragm dia and thickness and material property. Input pressure on diaphragm. Output: Max deflection of diaphragm. Kindly provide me...
View ArticleSimulation 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 ArticleParametric sweep and geometry change
a,b,theta_a and theta_b are global geometry parameters. theta_a = 2/a, and theta_b = 2/b. a,b,theta_a, and theta_b are all used in geometry creation. I am running a parametric sweep for parameters a...
View ArticleParameters calculation
Hello, I would like to ask if anyone know where I could find a full list or a list of the parameter comsol calculates when solving a model?. For example I know for piezoelectrics Y11 corresponds to the...
View ArticleTwo steps simulation
Hi, I am trying to model a variable capacitor, composed of a bottom (fixed) electrode and a suspended bridge. At the first step, I used DC voltage to make the fixed-fixed bridge deflects a certain...
View ArticleThermal expansion model.
I am trying to examine the stress distribution in a SiO2 film coated on a thick Si sample with a small Al bump on it, all heated to 600 K. I thought I built the model correctly, but a message that said...
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 ArticleCahn Hilliard type Equation not converging in COMSOL General PDE module
i Have been trying to run this model is COMSOL. I am using the PDE module to solve the problem.I keep geting this error Failed to find consistent intial values. Last time step is not converged....
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 ArticleVariable modifications between solution iterations
I'm developing a transient model using the Livelink interface. The model first calculates an initial solution for the first time window, then I would like to modify the state variable values due to...
View ArticleError-System matrix is zero
Failed to find a solution. System matrix is zero. Returned solution is not converged. Can anyone please explain me about this error?
View ArticleLithium ion battery 1D model: solver error
hi, I am trying to solve the Lithium ion battery model from the model library (li_battery_1d). I am always getting this error message while solving study1 in it .Please help me on this. Repeated error...
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