out of memory during assembly
Hi All, I am running a heat transfer with radiation, and the error message says "out of memory during assembly". Rigth now, I am using a workstation with 48GB memory. I check the element number, and it...
View ArticleDarcy Law using PDE
Hi, I'm trying to implement the Continuity Equation with Darcy law and the Energy equation using a PDE (base package). The Darcy equation in the continuity is u=-(k/mu)*d(p,x) where k is the...
View ArticleFunction for total spring constant in thin elastic layer
Hello, i'm a relatively new user with comsol, specially with the solid mechanics module. The goal in my work is to simulate the interaction between epoxy and fiber glass. I started with a 2D-model...
View ArticleEvaluate expression for different (specific) solutions
Hi all. Does anybody know how to evaluate expression for different solutions at the same time? I mean something like coupling integral between several modes. For example I have an eigenvalue problem...
View ArticleSurface reaction - diffusion: Robin condition
Hello, I am working on implementing a reaction-diffusion model. I have a particle in solution, where a reaction is occurring at the surface. I want to implement a Robin condition in the boundary of the...
View ArticleB-H curve of nonlinear material and constitutive relation
question1: In the calculation of magnetic field , I have a expression of B-H curve, is B=B(H). Then in the "Ampere's Law", When constitutive relation is "B=mu0*(H+M)", what shoud be filled in the...
View ArticleHow to deal with meshing for the thin bodies
Hi All, I am dealing with some very thin bodies, let's say, the thickness is 2mm, and width is 1000mm. I encounter difficulity to mesh these thin bodies. Do anyone have some suggestions? Thanks.
View ArticleSimulate an on-chip inductor
Hi :) I am new with Comsol and I am trying to draw an on chip inductor (the square shaped one) and then I want to study the electromagnetic effects and the properties (L and Q..) How can I draw the...
View ArticleHow can I find eigenmodes propagating in given direction?
Hi! I have a general question about eigenmode problem in RF module. How can i find only eigenmodes propagating in given direction? For example, let's consider an infinite number of parallel cylinders...
View ArticleChange the YOUNG’s modulus
I'm running this coupled heat transfer-structural model .The analysis is time dependent. In my model ,as the temperature rising, the metal has deformed (such as swelled).But in reality,the metal could...
View ArticleHow to define the zero potential at infinity boundary in electrostatisc of...
Hi, all I am not very familiar with COMSOL, just begin to learn, Looking forward to your help to address the issue "How to define the zero potential at infinity boundary in electrostatisc of ADDC...
View ArticleMissing geometries in a 2D plot group
Hi, My modell consists of a magnet between two ferrous pole shoes. In the air gap between those pole shoes is a ferrous triangle. I'm using the live-link interface to import this geometries from...
View Articlehow to apply AC voltage
respected sir i m creating a mems based disk resonator on comsol4.1 structure is drawn and i need to apply a AC VOLTAGE OF 2mV TO ONE OF THE ELECTRODE IN MY STRUCTURE. can anyone help me how to apply...
View ArticleApplying AC voltage
Hi all, I'm currently studying the electromechanical effects of a water droplet under AC/DC voltages. The water droplet is placed between two rectangular electrodes. I've applied a electric potential...
View ArticleWill the increase of the relative tolerance reduce the solving time ?
Dear all, as mentioned in the title, I would know if the change (specifically an increase) of the relative tolerance in Time Dependent solver (but also in Stationary solver, why not) will reduce the...
View ArticleEquilibrium composition
Can anyone help me solve this problem. I am not sure what I am doing wrong here. CH4 + CO2 <=> 2 CO + 2 H2 (equilibrium reaction) Assuming batch reactor constant volume and initially we have 1...
View Articlecontact plate element
Hi I have a problem how to model the contact between two plates en 2D, I need to know the conditions of contact between these plates (friction- sliding) these plates are modeling by their midlin plan,...
View Articlefinding capacitance
This is my first simulation in comsol . i don't know too much about this software.I am trying to find capacitance of a nano-FET in electrostatics module.for fringe field device is surrounded by air....
View ArticleFixed amount of confined fluids in presence of electric and magnetic field
Hi everyone, How can I apply electric and magnetic field on a fluid which is deposited on a plate and there is another plate at a some distance d apart from surface of liquid. (air above the fluid)....
View Articlesection view
I want to view a section through my geometry once the analysis has run. How to I go about this? Thanks, Christabel
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