Re: [FLASH-BUGS] possible bugs in Poisson routines

From: Artur Gawryszczak (gawrysz@camk.edu.pl)
Date: Thu Aug 07 2003 - 23:54:23 GMT

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    Hello,

    On Thursday 07 August 2003 23:12, Paul Ricker wrote:
    > The dust collapse problem requires isolated boundary conditions, which
    > are not supported for multigrid in 2D Cartesian coordinates. What
    > boundary conditions did you use for the 2D/3D multigrid case?

    I'm using `grav_boundary_type = "isolated"' in every run. Maybe this isn't
    supported, but both 2D and 3D setups does not complain about that. I made
    integrations once more (third or fourth time) and found the missing factor.
    I'm sorry about the mess.

    > For multipole, the problem is spherically symmetric, so you shouldn't
    > need to use such high mpole_lmax values. I suspect the problem in
    > this case is that, because of the high power of r for high multipole
    > order, errors in the computation of moments near the center are
    > leading to force errors there.

    Well, this was just an experiment. If it produces strange results in simple
    case, I'd rather not trust it and use multigrid submodule.

    -- 
    Best Regards,
            Artur
    



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