[FLASH-USERS] Checkerboard structure in magnetic field using USM solver

[Rukmani Vijayaraghavan]

Hi everyone,

I get a strange, unphysical feature in the magnetic field structure with 
the USM solver, seen in the attached slices of B_z and the magnetic 
pressure. These features, as you can see, track the block boundaries and 
look like a checkerboard of varying magnetic field strength (and sign?) 
in individual grid cells. I've tried modifying every possible USM solver 
switch, including the Riemann solver, order, slope limiter, prolongation 
method, steepening, etc. Using Riemann Solver = HLLC instead of HLLD 
makes things a little better, since HLLC is more diffusive, but the 
feature still eventually appears. Any advice on solving this or even 
minimizing its effects would be helpful!

Thanks,

Rukmani

-- 
Rukmani Vijayaraghavan
NSF Astronomy & Astrophysics Postdoctoral Fellow
University of Virginia
rukmani at virginia.edu

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