Vaibhav, 2016-09-15 12:29 GMT-04:00 Vaibhav Palkar <vaibhav_pal...@iitgn.ac.in>: > I'm indeed resetting my time step using get_status().delta_t_guess for the > next step. The step has not reached max_delta, coarsen_param is set to 1.2. > Any other reasons this can happen? I would need to see your code to understand why this happens. That part of the library is pretty simple, we just check that the error is less than coarsen_tol and if it is, delta_t_guess is multiplied by coarsen_param.
> The reason I was trying to avoid an implicit method is that it takes more > time per time step. I had earlier implemented my own version of the implicit > Euler(by formulating residuals and performing Newton iterations), which took > really long to run. The explicit methods run faster because they don't need > Newton iterations at every step. However, I guess I'll need to stick with > implicit methods if this doesn't work out. Implicit methods are more complicated and more expensive than explicit methods but if your problem is stiff, you may need to use a time step so small that it's worth using an implicit method. Also, generally, the Newton solver should converge pretty quickly because you start with a good initial guess. Best, Bruno -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
