Statistical properties of compressible hydrodynamic and magnetohydrodynamic turbulence
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چکیده
In this work, statistical properties of compressible hydrodynamic and magnetohydrodynamic turbulence are studied using direct numerical simulations. The properties of turbulent flows change when average flow velocities within the turbulence exceed the speed of sound in the medium. High flow velocities lead to the formation of shocks, and some of the base assumptions of turbulence theories of incompressible fluids no longer hold. This work presents a systematic study of the influence of flow parameters such as the sonic Mach number and the Alfvén Mach number on low-order statistical properties of isotropic, isothermal turbulence. Numerical results for both non-magnetic and magnetic turbulence are presented and compared to model predictions. In addition, this work suggests a turbulent cascade mechanism that is governed by momentum conservation in compressible turbulence.
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تاریخ انتشار 2011