[Users] Spacetime evolution with hydro refluxing

jensflo Jens.Mahlmann at uv.es
Thu Jan 10 09:54:27 CST 2019

Dear Erik,
    thank you very much for your mail. I hope I may bother you again
      with an Amateur question - I am surely misunderstanding something.
    The parameter Carpet::prolongation_order_space gives the
      interpolation order for the reconstruction of coarse grid points
      from the finely refined grids. In the par-examples of Refluxing I
      find Carpet::prolongation_order_space set to 1 and 3 (i.e.
      different values).  If for the refluxing the parameter Carpet::refinement_centering
      is set to "cell", then gridpoints should be aligned from fine to
      coarse grids. My question is if the prolongation_order_space makes
      a difference for "cell" centered refinement? This is the parameter
      which costs me a lot of time when changing to higher order, so I
      want to understand this.

    Thank you very much and my best!

-------- Original message --------From: Erik Schnetter <schnetter at cct.lsu.edu> Date: 1/10/19  01:59  (GMT+01:00) To: Jens Mahlmann <jensmahl at alumni.uv.es> Cc: Einstein Toolkit Users <users at einsteintoolkit.org> Subject: Re: [Users] Spacetime evolution with hydro refluxing 
If a horizon is not found, then I suspect insufficient resolution. You should be able to choose different prolongation operators for spacetime and hydrodynamics. Since the geometry is not refluxed, you could use a higher order operation there, while staying with linear interpolation for hydro.

On Wed, Jan 9, 2019 at 3:05 PM Jens Mahlmann <jensmahl at alumni.uv.es> wrote:


    Dear all,

    I have recently changed my hydro simulations to the Refluxing
      strategy implemented by Erik Schnetter. For this I have changed
      the standard configuration to a cell centred refinement,
        staggered boundaries and low order spatial prolongation for the
        hydro variables. Since then I experience problems with BSSN
      or, more specifically, the QuasilocalMeasures thorn (a=0.9 black
      hole). After an initially fine behaviour, no Eigenvector with
        value one is found and the spacetime gradually crashes. 

    I am still puzzled where this is coming from. Does anybody have
      some experience with the combination spacetime evolution + hydro
      refluxing, i.e. the somewhat different grid setup? I would be glad
      for any input to see where I start to fix my work.

    Thank you very much and my best from Valencia 




Users mailing list

Users at einsteintoolkit.org


Erik Schnetter <schnetter at cct.lsu.edu>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.einsteintoolkit.org/pipermail/users/attachments/20190110/a4b5281b/attachment.html 

More information about the Users mailing list