We show by direct numerical simulations (DNSs) that in different types of isotropic
turbulence, the fourth-order statistical invariants have approximately a linear relation, which …

In the present study, the effects of density variations on structures developing in an isotropic
incompressible turbulent flow are investigated. Statistical analyses are carried out on data …

In previous attempts of rational subgrid-scale (SGS) modeling by employing the Kolmogorov
equation of filtered (KEF) quantities, it was necessary to assume that the resolved-scale …

We rigorously show that the truncation at low wave numbers always leads to background
scalar-level anisotropy at large scales. Neither the resolution nor the spectral low-pass filter …

Energy development of decaying isotropic turbulence in a 3-D periodic cube with non-
rotating or rotating frames of reference is studied through direct numerical simulation using …

均匀各向同性湍流是一种最简单的湍流理想状态, 也是湍流基础理论研究的最重要对象之一.
为了用数值方法产生均匀各向同性湍流场, 一般采用Rogallo 提出的方法在谱空间生成初始场 …

The velocity derivative skewness and its budget equation are analysed in non-equilibrium
time-reversed turbulence. We show that the positive skewness is related to the behaviors of …

The two-dimensional hexagonal Fourier transform is introduced to reduce the background
anisotropy in the numerical calculations with periodic conditions. Comparing to traditional …

Turbulence has been a topic of scientific research for years. Characterized by unorganized
chaotic motion and irregular fluctuations, it persists as one of the most challenging topics in …

Homogeneous isotropic turbulence (HIT) is one of the simplest ideal turbulence states, and
is also one of the most important subjects in basic turbulence theory researches. HIT fields …