A nonlinear structural subgrid-scale closure for compressible MHD Part I: derivation and energy dissipation properties

Understand

Compressible magnetohydrodynamic (MHD) turbulence is ubiquitous in astrophysical phenomena ranging from the intergalactic to the stellar scales.

• In studying them, numerical simulations are nearly inescapable, due to the large degree of nonlinearity involved.
• However the dynamical ranges of these phenomena are much larger than what is computationally accessible.
• In large eddy simulations (LES), the resulting limited resolution effects are addressed explicitly by introducing to the equations of motion additional terms associated with the unresolved, subgrid-scale (SGS) dynamics.