Elliptic model for space-time correlations in turbulent shear flows
نویسندگان
چکیده
منابع مشابه
Elliptic model for space-time correlations in turbulent shear flows.
An elliptic model for space-time correlations in turbulent shear flows is proposed based on a second order approximation to the iso-correlation contours, while Taylor's hypothesis implies a first-order approximation. It is shown that the space-time correlations are mainly determined by their space correlations and the convection and sweeping velocities. This model accommodates two extreme cases...
متن کاملSpace-time correlations of fluctuating velocities in turbulent shear flows.
Space-time correlations or Eulerian two-point two-time correlations of fluctuating velocities are analytically and numerically investigated in turbulent shear flows. An elliptic model for the space-time correlations in the inertial range is developed from the similarity assumptions on the isocorrelation contours: they share a uniform preference direction and a constant aspect ratio. The similar...
متن کاملAsymmetry of temporal cross-correlations in turbulent shear flows
We investigate spatial and temporal cross-correlations between streamwise and normal velocity components in three shear flows: a low-dimensional model for vortex-streak interactions, direct numerical simulations for a nearly homogeneous shear flow and experimental data for a turbulent boundary layer. A driving of streamwise streaks by streamwise vortices gives rise to a temporal asymmetry in th...
متن کاملA low-dimensional model for turbulent shear flows
We analyse a low-dimensional model for turbulent shear flows. The model is based on Fourier modes and describes sinusoidal shear flow, in which the fluid between two free-slip walls experiences a sinusoidal body force. The model contains a total of nine modes, including modes describing the basic mean velocity profile and its modification, downstream vortices, streaks, and instabilities of stre...
متن کاملA model for the nonlinear dynamics of turbulent shear flows
We investigate the nonlinear dynamics of turbulent shear flows, with and without rotation, in the context of a simple but physically motivated closure of the equation governing the evolution of the Reynolds stress tensor. We show that the model naturally accounts for some familiar phenomena in parallel shear flows, such as the subcritical transition to turbulence at a finite Reynolds number and...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review E
سال: 2006
ISSN: 1539-3755,1550-2376
DOI: 10.1103/physreve.73.055303