Viscous Drag Reduction in Boundary Layers
Author :
Publisher : AIAA
Page : 542 pages
File Size : 21,61 MB
Release : 1990
Category : Boundary layer
ISBN : 9781600863783
Author :
Publisher : AIAA
Page : 542 pages
File Size : 21,61 MB
Release : 1990
Category : Boundary layer
ISBN : 9781600863783
Author : Peter Thiede
Publisher : Springer Science & Business Media
Page : 416 pages
File Size : 48,76 MB
Release : 2001-05-22
Category : Language Arts & Disciplines
ISBN : 9783540419112
This volume contains the proceedings of the CEAS/DragNet European Drag Reduction Conference 2000. The conference addressed the recent advances in all areas of drag reduction research, development, validation and demonstration including laminar flow technology, adaptive wing concepts, turbulent and induced drag reduction, separation control and supersonic flow aspects. This volume is of particular interest to engineers, scientists and students working in the aeronautics industry, research establishments or academia.
Author : Albert Gyr
Publisher : Springer Science & Business Media
Page : 617 pages
File Size : 18,88 MB
Release : 2012-12-06
Category : Science
ISBN : 3642509711
In 1976 a similar titled IUTAM Symposium (Structure of Turbulence and Drag Reduction) was held in Washington . However, the progress made during the last thirteen years as weil as the much promising current research desired a second one this year. In Washington drag reduction by additives and by direct manipulation of the walls (compliant walls and heated surfaces) were discussed. In the meantime it became evident that drag reduction also occurs when turbulence is influenced by geometrical means, e.g. by influencing the pressure distribution by the shape of the body (airfoils) or by the introduction of streamwise perturbances on a body (riblets). In the recent years turbulence research has seen increasing attention being focused on the investigation of coherent structures, mainly in Newtonian fluids. We all know that these structures are a significant feature of turbulent flows, playing an important role in the energy balance in such flows. However their place in turbulence theories as weil as the factors influencing their development are still poorly understood. Consequently, the investigation of phenomena in which the properties of coherent structures are alte red provides a promising means of improving our understanding of turbulent flows in general.
Author : Russell B. Sorrells
Publisher :
Page : 50 pages
File Size : 27,89 MB
Release : 1969
Category : Drag reduction
ISBN :
Author : Dennis O. Allison
Publisher :
Page : 124 pages
File Size : 17,48 MB
Release : 1996
Category : Aerodynamic load
ISBN :
Author : Stephen A. Whitmore
Publisher :
Page : 24 pages
File Size : 28,57 MB
Release : 1999
Category : Drag (Aerodynamics)
ISBN :
Drag reduction tests were conducted on the LASRE/X-33 flight experiment. The LASRE experiment is a flight test of a roughly 20-percent scale model of an X-33 forebody with a single aerospike engine at the rear. The experiment apparatus is mounted on top of an SR-71 aircraft. This paper suggests a method for reducing base drag by adding surface roughness along the forebody. Calculations show a potential for base drag reductions of 8 to 14 percent. Flight results corroborate the base drag reduction, with actual reductions of 15 percent in the high-subsonic flight regime. An unexpected result of this experiment is that drag benefits were shown to persist well into the supersonic flight regime. Flight results show no overall net drag reduction. Applied surface roughness causes forebody pressures to rise and offset base drag reductions. Apparently the grit displaced streamlines outward, causing forebody compression. Results of the LASRE drag experiments are inconclusive and more work is needed. Clearly, however, the forebody grit application works as a viable drag reduction tool.
Author : Rose McCallen
Publisher : Springer Science & Business Media
Page : 590 pages
File Size : 38,70 MB
Release : 2004-09
Category : Computers
ISBN : 9783540220886
This book includes the carefully edited contributions to the United Engineering Foundation Conference: The Aerodynamics of Heavy Vehicles: Trucks, Buses and Trains held in Monterey, California from December 2-6, 2002. This conference brought together 90 leading engineering researchers discussing the aerodynamic drag of heavy vehicles. The book topics include a comparison of computational fluid dynamics calculations using both steady and unsteady Reynolds-averaged Navier-Stokes, large-eddy simulation, and hybrid turbulence models and experimental data obtained from wind tunnel experiments. Advanced experimental techniques including three-dimensional particle image velocimetry are presented as well, along with their use in evaluating drag reduction devices.
Author : Peter Thiede
Publisher : Springer Science & Business Media
Page : 382 pages
File Size : 30,96 MB
Release : 2013-06-29
Category : Technology & Engineering
ISBN : 3540453598
------------------------------------------------------------ This volume contains the Proceedings of the CEAS/DragNet European Drag Reduction Conference held on 19-21 June 2000 in Potsdam, Germany. This conference, succeeding the European Fora on Laminar Flow Technology 1992 and 1996, was initiated by the European Drag Reduction Network (DragNet) and organised by DGLR under the auspice of CEAS. The conference addressed the recent advances in all areas of drag reduction research, development, validation and demonstration including laminar flow technology, adaptive wing concepts, turbulent and induced drag reduction, separation control and supersonic flow aspects. This volume which comprises more than 40 conference papers is of particular interest to engineers, scientists and students working in the aeronautics industry, research establishments or academia.
Author : Aroon Shenoy
Publisher : Springer Nature
Page : 196 pages
File Size : 15,46 MB
Release : 2020-03-25
Category : Technology & Engineering
ISBN : 303040045X
This book explains theoretical derivations and presents expressions for fluid and convective turbulent flow of mildly elastic fluids in various internal and external flow situations involving different types of geometries, such as the smooth/rough circular pipes, annular ducts, curved tubes, vertical flat plates, and channels. Understanding the methodology of the analyses facilitates appreciation for the rationale used for deriving expressions of parameters relevant to the turbulent flow of mildly elastic fluids. This knowledge serves as a driving force for developing new ideas, investigating new situations, and extending theoretical analyses to other unexplored areas of the rheology of mildly elastic drag reducing fluids.The book suits a range of functions--it can be used to teach elective upper-level undergraduate or graduate courses for chemical engineers, material scientists, mechanical engineers, and polymer scientists; guide researchers unexposed to this alluring and interesting area of drag reduction; and serve as a reference to all who want to explore and expand the areas dealt with in this book.
Author : Feng-Chen Li
Publisher : John Wiley & Sons
Page : 233 pages
File Size : 49,64 MB
Release : 2012-01-10
Category : Science
ISBN : 1118181115
Turbulent drag reduction by additives has long been a hot research topic. This phenomenon is inherently associated with multifold expertise. Solutions of drag-reducing additives are usually viscoelastic fluids having complicated rheological properties. Exploring the characteristics of drag-reduced turbulent flows calls for uniquely designed experimental and numerical simulation techniques and elaborate theoretical considerations. Pertinently understanding the turbulent drag reduction mechanism necessities mastering the fundamentals of turbulence and establishing a proper relationship between turbulence and the rheological properties induced by additives. Promoting the applications of the drag reduction phenomenon requires the knowledge from different fields such as chemical engineering, mechanical engineering, municipal engineering, and so on. This book gives a thorough elucidation of the turbulence characteristics and rheological behaviors, theories, special techniques and application issues for drag-reducing flows by surfactant additives based on the state-of-the-art of scientific research results through the latest experimental studies, numerical simulations and theoretical analyses. Covers turbulent drag reduction, heat transfer reduction, complex rheology and the real-world applications of drag reduction Introduces advanced testing techniques, such as PIV, LDA, and their applications in current experiments, illustrated with multiple diagrams and equations Real-world examples of the topic’s increasingly important industrial applications enable readers to implement cost- and energy-saving measures Explains the tools before presenting the research results, to give readers coverage of the subject from both theoretical and experimental viewpoints Consolidates interdisciplinary information on turbulent drag reduction by additives Turbulent Drag Reduction by Surfactant Additives is geared for researchers, graduate students, and engineers in the fields of Fluid Mechanics, Mechanical Engineering, Turbulence, Chemical Engineering, Municipal Engineering. Researchers and practitioners involved in the fields of Flow Control, Chemistry, Computational Fluid Dynamics, Experimental Fluid Dynamics, and Rheology will also find this book to be a much-needed reference on the topic.