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.

Getting different values each time running the same simulation

Please login with a confirmed email address before reporting spam

Hello all,

I am working on Comsol 5.3, using a time dependent ion flow model with 2 Partial differential equations. Everytime I run the same simulation (without any change) i get totally different graphs. Can anybody pls suggest me ways to solve this issue. Thank you so much..

With best regards Hari


2 Replies Last Post 2019年1月4日 GMT-5 09:39
Robert Koslover Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 6 years ago 2019年1月1日 GMT-5 00:29
Updated: 6 years ago 2019年1月1日 GMT-5 00:31

That's strange. By any chance, do you have (or did you define) any random number generators in your problem? That would be my first guess, since that would do it. But if not, then I am curious: Does it give different results if you clear the solution before you recompute? Does it give different results if you shutdown Comsol Multiphysics and then restart it? Does it give different results if you restart your computer between runs? How about if you save the file with two different names, load them both at the same time, and execute them both? Maybe you should post your model file to the forum!

-- Happy New Year.

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
That's strange. By any chance, do you have (or did you define) any random number generators in your problem? That would be my first guess, since that would do it. But if not, then I am curious: Does it give different results if you clear the solution before you recompute? Does it give different results if you shutdown Comsol Multiphysics and then restart it? Does it give different results if you restart your computer between runs? How about if you save the file with two different names, load them both at the same time, and execute them both? Maybe you should post your model file to the forum! -- Happy New Year.

Josh Thomas Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 6 years ago 2019年1月4日 GMT-5 09:39

I would check Initial Values of Variables Solved For. Are you sure each time you click compute you are starting from the same initial conditions?

-------------------
Best regards,
Josh Thomas
AltaSim Technologies
I would check Initial Values of Variables Solved For. Are you sure each time you click compute you are starting from the same initial conditions?

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.