East Asian Young Astronomers Meeting 2015
Time: February 9-12, 2015
Place: Taipei, Taiwan

Poster Presentation

Effects of Multiple-scale driving on turbulence statistics

Hyunju Yoo, Jungyeon Cho (Chungnam National University)

Turbulence is ubiquitous in astrophysical fluids such as the interstellar medium and the intracluster medium. In turbulence studies, it is customary to assume that fluid is driven on a single scale. However, in astrophysical fluids, there can be many different driving mechanisms that act on different scales. If there are multiple energy- injection scales, the process of energy cascade and turbulence dynamo will be different compared with the case of the single energy-injection scale. In this work, we perform three-dimensional incompressible/compressible magnetohydrodynamic turbulence simulations. We drive turbulence in Fourier space in two wavenumber ranges, 2<k<√12 (large scale) and 15<k<26 (small scale). We inject different amount of energy in each range by changing the amplitude of forcing in the range. We present the time evolution of the kinetic and magnetic energy densities and discuss the turbulence dynamo in the presence of energy injections at two scales. We show how kinetic, magnetic, and density spectra are affected by the two-scale energy injections and we discuss the observational implications. Furthermore, we have interest in effect of multiple-scale driving depending on different mach number on compressible turbulence.