Development of Turbulence in Postshock Regions

Abstract

Supersonic isothermal turbulence is ubiquitous in the interstellar medium. This work presents high-resolution AREPO hydrodynamical simulations of isolated shocks moving through supersonic turbulence to study the development and evolution of turbulence in the pre- and postshock regions. We find that shocks can amplify turbulent energy in the postshock region while inducing a preferential orientation for the vorticity. This results in the creation of anisotropic turbulence in the postshock region. Turbulent energy and dissipation are also strongly enhanced near the shock front. By applying typical scalings from the cold neutral medium to simulations, we find that shocks moving into turbulence on the scale of superbubbles can generate compressive flows on the order of 103 M⊙ Myr–1. Our results also show good agreement with related studies on turbulent fluctuations generated by shocks in pure fluid mechanics.