scispace - formally typeset
Search or ask a question
Topic

Flow separation

About: Flow separation is a research topic. Over the lifetime, 16708 publications have been published within this topic receiving 386926 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, a review of studies of laminar separated flows is presented, where the authors show that a mean flow pattern in a separated flow as well as its unsteady properties depend primarily on the instability and other "transitional" phenomena associated with a laminars separation.

298 citations

ReportDOI
30 Jul 2004
TL;DR: In this paper, the authors investigated the effect of roughness on the near-wall drag-producing turbulent structures and proposed control strategies to reduce momentum loss in rough-wall boundary layers.
Abstract: : The objective of this project is to improve our fundamental knowledge of turbulent flows over rough surfaces. Specifically, we hope to investigate the manner in which roughness affects the near-wall drag-producing turbulent structures, and to what extent surface roughness affects the outer part of rough-wall boundary layers. Ultimately we hope to use this knowledge to propose control strategies to reduce momentum loss in rough-wall boundary layers.

298 citations

Journal ArticleDOI
TL;DR: A model of the dynamic physical processes that occur in the near-wall region of a turbulent flow at high Reynolds numbers is described in this paper, where the hairpin vortex is postulated to be the basic flow structure of the turbulent boundary layer.
Abstract: A model of the dynamic physical processes that occur in the near-wall region of a turbulent flow at high Reynolds numbers is described The hairpin vortex is postulated to be the basic flow structure of the turbulent boundary layer It is argued that the central features of the near-wall flow can be explained in terms of how asymmetric hairpin vortices interact with the background shear flow, with each other, and with the surface layer near the wall The physical process that leads to the regeneration of new hairpin vortices near the surface is described, as well as the processes of evolution of such vortices to larger-scale motions farther from the surface The model is supported by recent important developments in the theory of unsteady surface-layer separation and a number of `kernel' experiments which serve to elucidate the basic fluid mechanics phenomena believed to be relevant to the turbulent boundary layer Explanations for the kinematical behaviour observed in direct numerical simulations of low Reynolds number boundary-layer and channel flows are given An important aspect of the model is that it has been formulated to be consistent with accepted rational mechanics concepts that are known to provide a proper mathematical description of high Reynolds number flow

298 citations

Journal ArticleDOI
TL;DR: In this article, the laminar separation bubble that forms on a NACA 663-018 airfoil model was surveyed at chord Reynolds numbers of 50,000-200,000 at angles of attack of 8-12 deg. The effects of various testing conditions on the separation bubble were isolated and the data were analyzed in relation to existing separation bubble correlations in order to test their low Reynolds number applicability.
Abstract: An experimental investigation was conducted in order to document the structure and behavior of laminar separation bubbles at low Reynolds numbers. Data of this type are necessary if the currently insufficient analytical and numerical models are to be improved. The laminar separation bubble that forms on a NACA 663-018 airfoil model was surveyed at chord Reynolds numbers of 50,000-200,000 at angles of attack of 8-12 deg. The effects of the various testing conditions on the separation bubble were isolated and the data were analyzed in relation to existing separation bubble correlations in order to test their low Reynolds number applicability. This analysis indicated that the chord Reynolds number and the disturbance environment strongly influence the experimental pressure distributions. These effects must be included in any analytic prediction technique applied to the low Reynolds number flight regime.

292 citations

Book
01 Jan 1990
TL;DR: In this article, the authors describe a procedure for the design and analysis of subsonic airfoils, including the evaluation of total lift, drag and moment coefficients, by means of a simple mathematical method from the properties of their velocity distribution.
Abstract: This book reflects the author's experience in the development of a computer program for the application of potential flow and boundary layer theories to the design and analysis of subsonic airfoils, including the evaluation of total lift, drag and moment coefficients. The design allows readers to compute the airfoil shape by means of a simple mathematical method from the properties of their velocity distribution, which can be specified in such a way that the boundary layer flow fulfills some given requirements. The most significant boundary layer phenomena such as laminar turbulent transition, laminar separation bubbles and boundary layer separation are considered. The first five chapters of this book describe a procedure for the design and analysis of subsonic airfoils. The data section contains 116 new airfoils for a wide range of Reynolds numbers and application requirements, including general aviation aircraft, tailless airplanes, gliders and propellers. The design features are explained and the input data for computer codes are given for all airfoils.

292 citations


Network Information
Related Topics (5)
Reynolds number
68.4K papers, 1.6M citations
94% related
Laminar flow
56K papers, 1.2M citations
91% related
Boundary layer
64.9K papers, 1.4M citations
91% related
Turbulence
112.1K papers, 2.7M citations
88% related
Vortex
72.3K papers, 1.3M citations
86% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023177
2022333
2021361
2020394
2019403
2018371