Quantcast
Channel: Latest Discussions - COMSOL Forums
Browsing all 5773 articles
Browse latest View live
↧

Boundary conditions don't seem to hold throughout simulation

Hello!I am currently working with the microfluidics module and using the laminar two phase flow, phase-field work. For my particular case, I want to use an outlet flow (e.g. 5 μL/min) while leaving the...

View Article


heat source location

I am modling moving laser heat source having guassian profile on flat plate of 5mm3mm200microns. I have two queries 1. I am getting moving laser sorce but it moving on corner of plate. However i want...

View Article


Calculate impedance variation

Hi,I would like to calculate impedance variation on a specified boundary based on time dependent study. The way of finding the impedance variation is to calculate elecrtical potential variation and...

View Article

rate coefficient import feature in plasma module??

Hi,I was wondering how I can efficiently import a large rate coefficient data for gaseous species (including ions and neutral species). In plasma module, it seems that I can only specify each reactions...

View Article

simulation of a reacting pipe

Hi friends I wanna simluate a pipe that contains a crude oil in it and we inject a high pressure air. Then they react and produce heat. But i dunno how to start, i will be happy if anyone could help...

View Article


COMSOL with matlab always stop looping

DERA All, I use COMSOL with matlab to run my model with a for-loop (change some parameters every time) . But, when the loop time achieved about 15, it will be ended, and says my computer's memory is...

View Article

Moving wall on outer boundary - specifying rotation

Hi everyone,I'm actually struggling to find out what's the proper way to model a 'moving wall' at a fluid-structure boundary that is in fact a rotational movement. For example, imagine a tubular...

View Article

Form union & form assembly = multiple geometries?

Hi,I am trying to use "form union" to some parts of my geometry, while I want to use "form assembly" to other parts of it. Is this possible within the same geometry, or one geometry can take only one...

View Article


how to model spring with variable stiffness in tension and compression

Hi . I am working on buckling of beams resting on springs.I found the spring foundation node in beams but it enables a constant stiffness. But in my case the spring has stiffness 30N/m in tension and...

View Article


Heat transfer surface to surface radiation

Hi, I've read the document provided for the topic Sun's Radiation Effect on Two Coolers Placed Under a Parasol at...

View Article

weak form

whether the dweak form in comsol has been canceled, only the weak form can be set

View Article

Question About The Application Builder

Dear all,I am running a model about pm-motor with a 2D model. I want to change some parameters of the motor, for example, the air gap in the pm-motor. However, the model I import without the...

View Article

Filling void space in assembly

I have a welded assembly that I have imported from Creo 5 that is a water-cooled part. I want to simulate the distortion from the internal space due to the water pressure. I've tried searching for this...

View Article


Applying constraint points for welding in assembly

I have searched info for welds, but only found info on modeling the welding process.I have a welded assembly for a water-cooled part, but not sure how to define constraints properly for the weld...

View Article

Why the sound intensity "acpr.I_mag" in posting is nothing?

I used the comsol pressure acoustic interface to simulate an ultrasonic cleaner, but selected the sound intensity in the post-processing results, all areas are 0, why?

View Article


Postprocessing access to timespecific values

Hey there, I have a big issue with the following topic.I created an time dependent model which includes a few ODEs calculating the biochemical concentrations. I need a small step size to get adequat...

View Article

How to do add a constant magnetic field to a physical domain

I am a newcomer,and I want to ask how to add an upward magnetic field in the figure below ,Thank you

View Article


Singularity Error

Hi.Repeated error test failures. May have reached a singularity. Time : 35489.13564466919 Last time step is not converged.How can this problem be solved?

View Article

Different solvers and their influence on the obtained results

Hello!I'm currently using COMSOL for a 3D microfluidics problem and I am performing a mesh refinement study. As I am quite new on the subject, I am only using different element sizes for a default...

View Article

Undefined variable , Failed to evaluate Jacobian of expression

Feature: Stationary Solver 1 (sol1/s1) Undefined variable.Variable: comp1.wGeometry: geom1Domain: 0 Failed to evaluate Jacobian of expression.Expression: comp1.w Failed to evaluate Jacobian of...

View Article
Browsing all 5773 articles
Browse latest View live