On 5/16/2015 10:33 AM, Matthew Knepley wrote:
1) The best thing you can do for solver convergence is to start with a
well-scaled system. Is there a reason why
you cannot non-dimensionalize your system?
Laziness/time, but yes I'll do this. Though this is a viscous flow
solver, so any non-dimensionalization will still lead to values
differing by 5+ orders of magnitude in certain areas.
3) If you have constraints on the variables, you might benefit from
using SNESVI
Perfect, thanks I wasn't aware of this. So SNESVIComputeVariableBounds
can take a function that say, prevents negative densities/pressures?
2) Writing a custom line search is easier than messing with TR in my
experience
I'm interested to hear more about this. I haven't done much work with
newton methods on this type of problem where overshoots lead to fatal
errors.
