Coupling Surface Charge Density from Electrostatics to Electrical Circuit
Hi, I have made a model of a varying overlap capacitor with an electric potential on one side as an electret. It seems to work with just ES and ALE but once I add in CIR and set the top electrodes as...
View Articlerestricted stress in time dependent problem
Hello evrybody, I m using a time dependent problem of a beam restricted at both ends. When we apply voltage or temperature, it produces stress greater than 500 MPa. Can anyone help me how to restricted...
View Articlevector form variables in PDE
What is the procedure to specify a dependent variable in PDE interface to be a vector rather than a scalar? In more specific terms, I'm trying to implement the vector wave equation in 3D using the...
View ArticleNeed Help: Solder Joint Estimation of Flip Chip
Dear All I'm a new for COMSOL. the case that i'm facing is a flip chip process. after read several samples, still could not figure it out what model/physics should to be used. hope to get some help...
View ArticleDeravites in 2D-axisymmetric models
Hi guys, I was wondering if we should add any extra parts for calculating the derivative of a variable in 2D-axisymmetric models? Under Definition ----Variables--If the goal is to define a new variable...
View ArticleAmazon Instance with Comsol
Hi, I knew this topic has been mentioned before in the forum, but I cannot find a definite answer. Has anyone been successful to run comsol on Amazon instances? Is there a detailed guide on this topic?...
View ArticleHow to assign a defined function to an electrode????
Hello Friends, Am working on AC/DC Module and new to comsol. Am trying to define a rectangular pulse of 1200v with a duration of 1ns to an electrode and i wish your kind assistance for the same. Thanks...
View ArticleHow can I find the flow velocity of a specific coordinate point
Dear all, I would like to ask how can I find the flow velocity of a specific point (x=105, y=2.5) in my channel (it is shown in the picture). In the graph, if I click at any random point I got 3...
View ArticlePolynomial Issue with User-defined Variables
I have a 2D rectangular geometry that has porosity and permeability values dependent on x-coordinate. Polynomial expressions are used to define the local porosity and permeability. However, COMSOL does...
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 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 Articleelectro-convection
Can Comsol solve an electroconvection problem? To clarify: a polar gas or liquid moves in nonuniform electric field. Thus, we need to solve for electrostatics, and the known field distribution will...
View ArticleDefining port, identity pair and PML layer
Dear Friend, Currently i am using comsol 4.3 version, i am totally new about it. could you suggest me how can i define port i,identity pair and also PML at same time in my model. it was works nicely in...
View ArticleConvergence problem in RF module
I am doing some plasmonics simulation using silver nano particles in comsol. For silver particle convergence is either very very slow or there is no convergence in most cases for some specific...
View Articlequestions on point source phase
Hi all, I am trying to simulate the interference of two point sources. I want them to be out-of-phase. In Helmholtz equation model, the two sources are given as weak contribution. One of them is...
View ArticleError in electric gap
Hey. Can anyone tell me what this means: Feature TCL1 dos not support model imput? Appears to me when I used electrical gap in ac / dc / electrostatics. Thank you.
View ArticleCylindrical anisotropic stiffness
Hi, Problem: Imagine a cylindrical shell, with a certain wall thickness. The material properties of the shell have an isotropic density (rho) and an anisotropic stiffness described by a constant radial...
View ArticleMeaning of "node" vs. "vertex" vs. "degree of freedom" for linear finite...
Hi there, can anybody tell me what COMSOL means by the word "node" in contrast to "vertex" or "degree of freedom" when it comes to the discretization? I have...
View ArticleSplit solid into two domains
Hi, I have a 3D model that I've imported into COMSOL. In Solidworks, I have two features that are separate, however, when imported into COMSOL, they become a single domain and a single geometry...
View ArticleHow to evaluate field data in specific point
Hello everyone, I want to simulate particle-particle magnetic interaction in particle tracing. I wrote down an equation for calculation of interaction force. I need to know other points magnetic field...
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