Minimal multi-scale dynamics of near-wall turbulence
نویسندگان
چکیده
Abstract
منابع مشابه
Low-dimensional dynamics of near-wall turbulence
Wall-bounded turbulent shear flows are perhaps the last area in ‘classical’ incompressible turbulence in which there still are open questions about basic physical mechanisms. There are two competing conceptual models. In the first one, wall turbulence is just a modification of ordinary shear turbulence occuring when the latter is a near wall, and is therefore dependent on the prior existence of...
متن کاملLarge-scale influences in near-wall turbulence.
Hot-wire data acquired in a high Reynolds number facility are used to illustrate the need for adequate scale separation when considering the coherent structure in wall-bounded turbulence. It is found that a large-scale motion in the log region becomes increasingly comparable in energy to the near-wall cycle as the Reynolds number increases. Through decomposition of fluctuating velocity signals,...
متن کاملMulti-scale Nonlinear Turbulence Dynamics Studies
Critical gradient transport dynamics, breaking of gyro-Bohm transport scaling, transport bifurcation, and transport barrier formation all have a profound effect on confinement in magnetic fusion devices, and are thought to be both generated and regulated by the nonlinear interaction between gradient-driven small scaled ( k!"s <1) drift turbulence and larger meso-scaled structures such as zonal ...
متن کاملNonlinear RDT theory of near-wall turbulence
A WKB method was recently used to extend rapid distortion theory (RDT) to initially inhomogeneous turbulence strained by irrotational mean flows [S.V. Nazarenko, N. Kevlahan, B. Dubrulle, J. Fluid Mech. 390 (1999) 325]. This theory takes into account the feedback of turbulence on the mean flow, and it was used by Nazarenko et al. to explain the effect of strain reduction caused by turbulence ob...
متن کاملOn the near-wall characteristics of acceleration in turbulence
The behaviour of fluid-particle acceleration in near-wall turbulent flows is investigated in numerically simulated turbulent channel flows at low to moderate Reynolds numbers, Reτ =180∼ 600. The acceleration is decomposed into pressure-gradient (irrotational) and viscous contributions (solenoidal acceleration) and the statistics of each component are analysed. In near-wall turbulent flows, the ...
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: Journal of Fluid Mechanics
سال: 2021
ISSN: ['0022-1120', '1469-7645']
DOI: https://doi.org/10.1017/jfm.2020.1182