Regions of the Boundary Layer Flows may be distinguished as laminar or turbulent on the basis of their Reynolds number, Ul/ν, where l is some relevant length scale (e.g., depth of a river, diameter of a particle) (see UNIDIRECTIONAL AQUEOUS FLOW). Low Reynolds number flows are laminar,...
Prandtl's boundary-layer approximation is discussed and a strategy for coping with boundary layers with more complicated boundary conditions is explained and some useful empirical formulations provided. These "extra rates of strain" not only necessitate some additional empiricism in turbulence models for ...
turbulent boundary layer 美 英 un.湍流边界层区;紊流边界层 英汉 un. 1. 湍流边界层区 2. 紊流边界层 释义: 全部,湍流边界层区,紊流边界层
Coherent features in theturbulent boundary layerare also found in the outer, inertial-dominated regions as well, principally the log-layer. Such structures in the outer flow are larger than those in the near-wall cycle, and manifest themselves more significantly for highReτwith a well-developed...
Comparison between rough- and smooth-wall turbulent boundary layers Measurements in a zero-pressure-gradient turbulent boundary layer over a mesh-screen rough wall indicate several differences, in both inner and outer regio... P.-. Krogstad,RA Antonia,LWB Browne - 《Journal of Fluid Mechanics》 ...
湍流边界层结构 Turbulent Boundary Layer Structure
(1) laminar separation, when the laminar boundary layer on the cylinder separates and transition to turbulence occurs in the shear layer, and (2) turbulent separation, when the boundary layer naturally transitions to turbulent, and then... X Wu,A Sharma,M Jafari,... - Aiaa Aerospace Sciences...
The sign of is obtained from the scalar product of the velocity vector at the first node above the wall and at the boundary layer edge [see Cousteix and Houdeville (1981)] and is used to exclude regions of separated flow. The value is used. Hence the extra term is not active in ...
turbulent tangential stresses are used to construct a self-similar reverse flow of an incompressible fluid that, depending on the values of the empirical constants occurring in it, can be realized either behind the separation point of a turbulent boundary layer or in front of its point of ...
7.5.2 Turbulent boundary layer flow As mentioned previously, even when the flow becomes turbulent in the boundary layer, there exists a thin sub-layer close to the surface in which the flow is laminar. This layer and the fully turbulent regions are separated by a buffer layer, as shown sche...