Daniel, Thank you. I am a bit surprised that the CentralDifference basically matches the hybrid method, and is more accurate than upwind.
Kris On Tue, Apr 26, 2016 at 8:22 AM, Daniel Wheeler <daniel.wheel...@gmail.com> wrote: > Hi Kris, > > Good to hear from you again and a very nicely coded example. > > I think it's a solver issue. I tried the LU solver and it gives > perfect results. See > https://gist.github.com/wd15/affe4d82cc2a189d894a7d774e4bc00b. > > This might suggest that we need to change the default solver when > using the central difference scheme. > > Cheers, > > Daniel > > On Mon, Apr 25, 2016 at 11:54 AM, Kris Kuhlman > <kristopher.kuhl...@gmail.com> wrote: > > I am trying to understand the convection terms available in fipy through > a > > simple steady-state problem. I am surprised at the divergence of the > > CentralDifferenceConvectionTerm, is this to be expected? As the > > discretization in the mesh is made finer, the solution gets worse!? > > > > The problem is: \frac{\partial^2 u}{\partial x^2} - v \frac{\partial > > u}{\partial x} = 0 > > > > The script at the link below compares the solution using different > > ConvectionTerms, and plots the figures attached for different values of > nx. > > For larger values of v, the solution diverges even more and becomes > > oscillatory. > > > > https://gist.github.com/klkuhlm/07f9eaf52b24e103f60ae213c0944c21 > > > > Is this expected behavior? > > > > Kris > > > > > > _______________________________________________ > > fipy mailing list > > fipy@nist.gov > > http://www.ctcms.nist.gov/fipy > > [ NIST internal ONLY: https://email.nist.gov/mailman/listinfo/fipy ] > > > > > > -- > Daniel Wheeler > _______________________________________________ > fipy mailing list > fipy@nist.gov > http://www.ctcms.nist.gov/fipy > [ NIST internal ONLY: https://email.nist.gov/mailman/listinfo/fipy ] >
_______________________________________________ fipy mailing list fipy@nist.gov http://www.ctcms.nist.gov/fipy [ NIST internal ONLY: https://email.nist.gov/mailman/listinfo/fipy ]
