multiphase flow with moving interface combined with diffusion
I'm working on a simulation of two droplets in air coalescing into one combined droplet in which I want to follow in time the mass transport of a species C in one droplet into the coalesced droplet....
View Articleupdating a nested parametric sweep
Hi I use nested parametric sweep and once in a while after the model has been solved, I would like to add one or two additional values to my parameters to fill the gap between them or increase the...
View ArticleMaking unions, intersections and such
Hello, this is the question regarding the "Internal error in geometry decomposition" message that I'm consistently getting. What I'm trying to build is a 3D RVE of particulate composite (see attached...
View ArticleDifference between "Porous Media and Subsurface Flow" and "Poroelasticity...
I am a little confused by two physical module, the first one is Fluid Flow-----Porous Media and Subsurface Flow, and the second one is Structural Mechanics--------Poroelasticity (Poro). What is the...
View ArticleInsulation testing
Hi, I,m doing my project on stator bar winding testing (insulation testing),I want simulate by Comsol.But still i don't know can i do with comsol or not? as example how can measure PD(partial...
View Articletry/catch in matlab for COMSOL
I am doing a parametric sweep in COMSOL with the geometry. The problem is, it is a large parameter space and a few combinations which would be unreasonable to check give an error. It is a stationary...
View Articlehow to model interface position when filling a channel
Hey, I'm quite new to comsol and so my questions are maybe simple to answer - but not for me yet. For my work I try to model a microchannel with 1mm*1mm crossarea and 5cm long, where water is pumped in...
View Articlesolving helmholtz equation
I wish to solve Helmholtz equation for an Axi-symmetric geometry. The problem geometry consists of a excitation source a tube and air box (all rectangles). Is it possible in equation based modeling?....
View ArticleTED in MEMS resonator
Hi I am new to COMSOL. I was trying the Thermoelastic damping in MEMS resonator model [it was done on 3.5 but my version is 4.2a] provided by the comsol. Although I get the similar eigenfrequencies but...
View ArticleHow to define a dispersive material as a function of COMSOL predefined...
Hi: I defined a dispersive material function (frequency dependent relative permittivity) in Global Definition. Function name: LD_real Expression: ff E-14+0.6 Argument: ff Argument unit: Hz Function...
View ArticleReverse Joule Heating
Hi. This is my first time using Comsol so please bare with me :) I'm doing a model of a HV power cable, that heats up due to the current flowing through it. I know that the temperature of the isolation...
View ArticleTransient Hot Wire Method
Hi Everyone! I'm new on COMSOL so I don't know too much yet. I need to simulate the transient hot wire method, I don't know how to start with, and I cannot find any example. Could somebody help me with...
View ArticleRegular Meshing
Hi all, I've been asked to create a regular mapped mesh for a cube which has faces of 10 by 10 square areas throughout the whole of the cube. I'm applying a magnetic field to the cube and I wanted to...
View Articledifference in results when the duration of the model was changed
Hi! I ran the same model for a longer time (Rotating Machinery, Laminar Flow module) and the resulting velocity and pressure are different. Which one should I trust? Why does this happen? For the 2 s...
View ArticleHow is the penalty factor used in the penalty method?
I am modeling a transient contact problem using the penalty method instead of the augmented Lagrangian method. How does COMSOL use the penalty factor when the penalty method is being used? I understand...
View ArticleDilute species transport concentration condition
Hi I wonder why the "Concentration" condition in the dilute species transport model is of type "boundary" and not "domain", since its unit is in "Mole/Volume". Why does this make sense? How should this...
View ArticleHow to simulate the dynamic process of the shelled microbubble using COMSOL
We plan to simulate the dynamic process of the shelled microbubble with diameter of 5um and thickness of 10-100nm, which vibrates inside the ultrasound beam with center frequency of 1MHz. There is one...
View ArticleTransient Laminar Fluid flow and heat transfer in Porous media
Hi I'm trying to model coupled physics of transient steam flow through a porous medium and heat transfer between steam and the porous medium material and wall. The porous medium has a low thermal...
View ArticleCharge conservation
Hi, I am new to COMSOL and I don't think I really understand where to use "Charge conservation" in the ES and in Plasma modules. Going through tutorials show that people use it if you have a dielectric...
View ArticleCall functions in 4.3a
Hi I created an interpolation fonction in the global definitions node. I need to use that function as an excitation in a bondary condition and simulate according to that interpolation. So, I put "Int1"...
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