Author: J. J. Ginoux Publisher: ISBN: Category : Languages : en Pages : 65
Book Description
An experimental study of a 3D skewed shock wave laminar boundary layer interaction has been carried out. The test configuration was a flat/finned plat arrangement with sharp leading edge fins having 4, 6 and 8 deg incidence relative to the free stream. The flat plate laminar boundary layer had thickness between 1.1 and 2.2 mm depending on test conditions. The unit Reynolds numbers used were 1.2 million and 2.4 million. Experimental surface data represented as surface flow visualizations and pressure distributions are presented for all test conditions. All tests were carried out at a nominal free stream Mach number of 2.25 and under approximately adiabatic wall conditions. The experimental results indicate that extended separation occurs even for the smallest wedge incidence, i.e., for a pressure ratio of 1.27 and that the extent of upstream influence is much larger in this 3D interaction than in comparable 2D interactions. Preliminary theoretical investigations show that an integral method is not suited for the study of the present interaction. The new implicit corrected viscosity method for solving the compressible Navier-Stokes equations can yield convergence speeds of order unity under suitable chosen conditions. (Author).
Author: George R. Inger Publisher: ISBN: Category : Languages : en Pages : 37
Book Description
The objective of this research is the basic theoretical investigation of three-dimensional pressure, skin friction, and heat transfer disturbances in both laminar and turbulent boundary layer flows including viscous-inviscid interaction effects, separation, and reattachment. A sound understanding of these phenomena is required in modern aerodynamic design analyses of high-speed flight vehicles. The primary emphasis in these studies has been to seek a basic physical understanding of the underlying fluid behavior by means of analytically-oriented methods; in this way, the results can be used to guide and interpret concurrent experimental and computationally-oriented investigations. This inquiry has focused on two parallel paths of investigation: three-dimensional, viscous-inviscid interaction phenomena within turbulent boundary layers in supersonic flow due to impinging swept shock and/or 3-D surface deflections, and streamwise vortex-disturbance mechanisms within laminar or turbulent boundary layers that are either separated or attached.
Author: P. S. Klebanoff Publisher: ISBN: Category : Languages : en Pages : 120
Book Description
An experimental investigation is described that is directed toward extending the technical database and furthering our understanding of boundary layer transition induced by three-dimensional roughness elements. The investigation was carried out in an unsteady wind tunnel, principally with hemispherical roughness elements, in a well characterized zero-pressure gradient laminar boundary layer on a flat plate. Attention was directed toward the following aspects of the behavior of a three dimensional roughness element: (1) the critical Reynolds number of transition and the effect of aspect ratio thereon, (2) eddy generation is steady and unsteady flows, (3) is the fundamental process stability governed, and (4) the evolutionary change in mean velocity and intensity of the velocity fluctuation associated with the transition to fully developed turbulent flow.
Author: H.F. Fasel Publisher: Springer Science & Business Media ISBN: 3662039974 Category : Science Languages : en Pages : 703
Book Description
The origins of turbulent flow and the transition from laminar to turbulent flow are among the most important unsolved problems of fluid mechanics and aerodynamics. Besides being a fundamental question of fluid mechanics, there are any number of applications for information regarding transition location and the details of the subsequent turbulent flow. The JUT AM Symposium on Laminar-Turbulent Transition, co-hosted by Arizona State University and the University of Arizona, was held in Sedona, Arizona. Although four previous JUT AM Symposia bear the same appellation (Stuttgart 1979, Novosibirsk 1984, Toulouse 1989, and Sendai 1994) the topics that were emphasized at each were different and reflect the evolving nature of our understanding of the transition process. The major contributions of Stuttgart 1979 centered on nonlinear behavior and later stages of transition in two-dimensional boundary layers. Stability of closed systems was also included with Taylor vortices in different geometries. The topics of Novosibirsk 1984 shifted to resonant wave interactions and secondary instabilities in boundary layers. Pipe- and channel-flow transition were discussed as model problems for the boundary layer. Investigations of free shear layers were presented and a heavy dose of supersonic papers appeared for the first time. The character of Toulouse 1989 was also different in that 3-D boundary layers, numerical simulations, streamwise vortices, and foundation papers on receptivity were presented. Sendai 1994 saw a number of papers on swept wings and 3-D boundary layers. Numerical simulations attacked a broader range of problems.
Author: V. C. Patel Publisher: ISBN: Category : Turbulent boundary layer Languages : en Pages : 32
Book Description
Three-dimensional thin boundary-layer equations for laminar and turbulent flows are solved by two different numerical schemes. The methods are applied to the flow over bodies of revolution at incidence and the results are compared with the available experimental data in order to study the range of validity of the classical boundary-layer approximations in regions of increasing circumferential gradients and flow reversal associated with the early stages of a free-vortex type of separation. Comparison with the DFVLR 6:1 spheroid data of Meier et al and the 4:1 combination-body data of Ramaprian, Patel and Choi indicate that the methods perform well in regions where the boundary layer remains thin but the predictions deteriorate as the boundary layer thickens. The results point out the need for the development of methods of handle thick boundary layers and viscous-inviscid interactions. (Author).
Author: Hermann Schlichting (Deceased) Publisher: Springer ISBN: 366252919X Category : Technology & Engineering Languages : en Pages : 814
Book Description
This new edition of the near-legendary textbook by Schlichting and revised by Gersten presents a comprehensive overview of boundary-layer theory and its application to all areas of fluid mechanics, with particular emphasis on the flow past bodies (e.g. aircraft aerodynamics). The new edition features an updated reference list and over 100 additional changes throughout the book, reflecting the latest advances on the subject.
Author: E. A. Eichelbrenner Publisher: ISBN: Category : Languages : en Pages : 101
Book Description
The report is chiefly dedicated to the behavior of separation and reattachment in three-dimensional turbulent boundary layers, in particular on ellipsoids and annular wings.
Author: J. J. Ginoux
Author: Von Karman Institute for Fluid Dynamics
Author: George R. Inger
Author: P. S. Klebanoff
Author: H.F. Fasel
Author: V. C. Patel
Author: 
Author: Hermann Schlichting (Deceased)
Author: E. A. Eichelbrenner
Author: