Spatio temporal analysis of waves in compressible magnetohydrodynamics turbulence

Maia Brodiano

Using direct numerical simulations (DNSs), the interaction between linear waves and turbulence under the compressible MHD (CMHD) approach was studied. A set of DNSs in three dimensions for a spatial resolution of 1283 and 2563 were performed and a parametric study was carried out varying the Mach number, the mean magnetic field and the compressibility amplitude of the forcing. Spatio-temporal spectra of the magnetic energy were built and analyzed, allowing for direct identification of all wave modes in a turbulent system and quantification of the amount of energy in each mode as a function of the wavenumber. In addition, making use of an integration method, we accurately quantified the amount of energy present in each of the normal modes of the CMHD model. Thus, linear waves were detected, that is Alfvén waves and fast and slow magnetosonic waves.