Menu

Discussion Forum

New Discussion
查找

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Convergence and time step solver

Posted 2015年12月15日 GMT-5 01:53 Results & Visualization, Studies & Solvers Version 4.3 4 Replies

Badri Suhaini
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi all,
How's everyone? :D

Anyway,
Just want to know, what does that curvy distorted line at the end of the diagram shows?
Does it mean I have instability convergence? too large time step?

how do I solve this? I am getting singularity error everytime.

I followed "singularity.error" on the discussion forum and the comsol employee at the end of the discussion

Regards,
Badri

Attachments:

4 Replies Last Post 2015年12月17日 GMT-5 02:12
Krishnaswamy Veluswamy
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 9 years ago 2015年12月15日 GMT-5 13:31
Hi,

Even I am facing facing the same issue with Time dependent optimization.

However, reducing the time step, doesnt going really affect the error, but you get the error after a prolonged time. (I got it like that), however for many it worked by reducing the time step.

Whatever the timestep you give in the solver, its just for post processing and it has nothing to do with the calculation (I hope so), as the comsol has inbuilt time stepping which will calculate at those time steps.

I still puzzled at the error. post me a msg if u get rid of this error.
Hi, Even I am facing facing the same issue with Time dependent optimization. However, reducing the time step, doesnt going really affect the error, but you get the error after a prolonged time. (I got it like that), however for many it worked by reducing the time step. Whatever the timestep you give in the solver, its just for post processing and it has nothing to do with the calculation (I hope so), as the comsol has inbuilt time stepping which will calculate at those time steps. I still puzzled at the error. post me a msg if u get rid of this error.
Badri Suhaini
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 9 years ago 2015年12月15日 GMT-5 18:10
Hello

I solved the error already,
I did it by reducing the time step in my "Study: Time-dependent" for example by making range (0,0.5,1) to range (0,0.1,1).

And I also followed the "improving convergence in nonlinear time dependent model" on the COMSOL discussion. (www.comsol.com/support/knowledgebase/1127/)

Do you know what it means by convergence? What does it value shows actually from the image that I have attached? What does it mean if the convergence decreases or increases as time goes on?

Regards,
Badri
Hello I solved the error already, I did it by reducing the time step in my "Study: Time-dependent" for example by making range (0,0.5,1) to range (0,0.1,1). And I also followed the "improving convergence in nonlinear time dependent model" on the COMSOL discussion. (http://www.comsol.com/support/knowledgebase/1127/) Do you know what it means by convergence? What does it value shows actually from the image that I have attached? What does it mean if the convergence decreases or increases as time goes on? Regards, Badri
Krishnaswamy Veluswamy
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 9 years ago 2015年12月16日 GMT-5 04:30
Hi,

There is already an discussion on convergence in the forum,

here you go for the link,

www.comsol.com/community/forums/general/thread/35375/

Hope it helps.
Hi, There is already an discussion on convergence in the forum, here you go for the link, http://www.comsol.com/community/forums/general/thread/35375/ Hope it helps.
Badri Suhaini
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 9 years ago 2015年12月17日 GMT-5 02:12
Thanks
Thanks

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content