Speaker
Mr
Fabio Bacchini
(KU Leuven)
Description
We present a new Lagrangian, multi-dimensional, fluid PiC code for MHD space simulations, based on the FLIP-MHD method designed by Brackbill. In contrast with standard kinetic PiC codes, Slurm uses particles as carriers of all the conserved quantities, while advancing the macroscopic properties of the plasma on a Lagrangian grid. The communication between particles and grid is allowed through bilinear interpolation: at each cycle, the grid properties are initialized from the particles, advanced by solving the system of Lagrangian MHD equations and interpolated back to the particle domain. Then, the particles are advanced on the phase space by solving the equations of motion in finite difference form.
Slurm aims at solving the two main problems affecting FLIP-MHD, namely the arising of the ringing instability and the high computational cost due to the need of solving a Poisson's equation for the magnetic field scalar potential.
The ringing instability is efficiently suppressed by allowing the particles to evolve their volume throughout the computation. This is done by implementing the same strategy adopted by Bardenhagen et al. (2004) in the GIMP method for computational mechanics. The second problem implies to find a suitable strategy for maintaining the div(B)=0 constrain.
Possible practical applications of the new method are presented, along with some results obtained from test cases and simulations of CME-driven shocks.
Primary author
Mr
Fabio Bacchini
(KU Leuven)
Co-authors
Dr
Alessandro Bemporad
(OATo - INAF)
Prof.
Giovanni Lapenta
(KULeuven)
