title: Cascade of kinetic energy in three-dimensional compressible turbulence.
abstract: The conservative cascade of kinetic energy is established using both Fourier analysis and a new exact physical-space flux relation in a simulated compressible turbulence. The subgrid scale (SGS) kinetic energy flux of the compressive mode is found to be significantly larger than that of the solenoidal mode in the inertial range, which is the main physical origin for the occurrence of Kolmogorov's -5/3 scaling of the energy spectrum in compressible turbulence. The perfect antiparallel alignment between the large-scale strain and the SGS stress leads to highly efficient kinetic energy transfer in shock regions, which is a distinctive feature of shock structures in comparison with vortex structures. The rescaled probability distribution functions of SGS kinetic energy flux collapse in the inertial range, indicating a statistical self-similarity of kinetic energy cascades.
authors.affiliation: State Key Laboratory for Turbulence and Complex Systems, Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing 100871, China.
authors.forename: Jianchun
authors.initials: J
authors.lastname: Wang
authors.forename: Yantao
authors.initials: Y
authors.lastname: Yang
authors.forename: Yipeng
authors.initials: Y
authors.lastname: Shi
authors.forename: Zuoli
authors.initials: Z
authors.lastname: Xiao
authors.forename: X T
authors.initials: XT
authors.lastname: He
authors.forename: Shiyi
authors.initials: S
authors.lastname: Chen