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.

time variable

Please login with a confirmed email address before reporting spam

Hi everybody,
someone can tell me how to shift the time variable "t" in Comsol 3.5a. In other words, I need to know how it is possible to change, for example, the time variable from <t> to <tau=t-100>. the fact is that I need to solve a final value problem, instead of initial value problem.
Thanks

Luigi

2 Replies Last Post 30 juil. 2010, 05:11 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 29 juil. 2010, 16:21 UTC−4
Hi

I believe too that you an simply inverte the time asw you are saying if you want a final value solution depending on the time. Pls report back it's always useful to hear from such tests

--
Good luck
Ivar
Hi I believe too that you an simply inverte the time asw you are saying if you want a final value solution depending on the time. Pls report back it's always useful to hear from such tests -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 30 juil. 2010, 05:11 UTC−4
Hi Ivar, it's not clear to me what you mean when you write "time asw". Anyway, I'm going to solve the problem in a very simply way. In fact, i think that a final value problem, tipycally involved in case of minimization problems with conjugate gradient method, can be solved like an initial value problem imposing the final value as initial value. At the end of simulation, I only have to change the time variable from "t" to "Tfinal -t" in the report.
Did you mean this way in your reply?
Thanks

Luigi
Hi Ivar, it's not clear to me what you mean when you write "time asw". Anyway, I'm going to solve the problem in a very simply way. In fact, i think that a final value problem, tipycally involved in case of minimization problems with conjugate gradient method, can be solved like an initial value problem imposing the final value as initial value. At the end of simulation, I only have to change the time variable from "t" to "Tfinal -t" in the report. Did you mean this way in your reply? Thanks Luigi

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.