Viscous Drag Measurement and Its Application to Base Drag Reduction

Download Viscous Drag Measurement and Its Application to Base Drag Reduction PDF Online Free

Author :
Publisher :
ISBN 13 : 9781423510048
Total Pages : 102 pages
Book Rating : 4.5/5 (1 download)

DOWNLOAD NOW!


Book Synopsis Viscous Drag Measurement and Its Application to Base Drag Reduction by : Robert K. Decker

Download or read book Viscous Drag Measurement and Its Application to Base Drag Reduction written by Robert K. Decker and published by . This book was released on 2002-05 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study two important topics have been investigated. First, a new automation procedure has been developed to detect fringe patterns in oil- film interferograms. The procedure combines a windowed Fourier transform and a cross correlation technique to determine regions where fringes are likely to reside. The cross correlation of a single cycle cosine function and the original intensity produce a filtered result that isolates the information being sought. The automation procedure is able to capture approximately 75% of the fringes in an image but additional refining of the technique could increase this percentage. Second, the effect of viscous fore-body drag on base drag has been investigated on a 2-D ramp model. Measurements made during the study include oil-film interferometry and hot-wire anemometry for viscous fore-body drag, and pressure measurements on the fore-body and base for fore-body and base drag. The results of this investigation show that an increase in viscous fore-body drag has very little effect on base drag, which contrasts previous studies where increases in viscous fore-body drag tended to decrease base drag. This means that a simple jet pumping mechanism is not the sole effect responsible for base drag reduction in this type of geometry. Hot-wire measurements in the wake of the model show that the flow in the base region is devoid of a dominant shedding frequency. It may be possible that the boundary layer somehow affects the vortex shedding mechanism but further investigations would be necessary to demonstrate that this is true.

Viscous Drag Reduction

Download Viscous Drag Reduction PDF Online Free

Author :
Publisher : Springer
ISBN 13 : 1489955798
Total Pages : 497 pages
Book Rating : 4.4/5 (899 download)

DOWNLOAD NOW!


Book Synopsis Viscous Drag Reduction by : C. Sinclair Wells

Download or read book Viscous Drag Reduction written by C. Sinclair Wells and published by Springer. This book was released on 2013-12-20 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Viscous Drag Reduction in Boundary Layers

Download Viscous Drag Reduction in Boundary Layers PDF Online Free

Author :
Publisher : AIAA
ISBN 13 : 9781600863783
Total Pages : 542 pages
Book Rating : 4.8/5 (637 download)

DOWNLOAD NOW!


Book Synopsis Viscous Drag Reduction in Boundary Layers by :

Download or read book Viscous Drag Reduction in Boundary Layers written by and published by AIAA. This book was released on 1990 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt:

A Base Drag Reduction Experiment on the X-33 Linear Aerospike SR-71 Experiment (LASRE) Flight Program

Download A Base Drag Reduction Experiment on the X-33 Linear Aerospike SR-71 Experiment (LASRE) Flight Program PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 24 pages
Book Rating : 4.:/5 (317 download)

DOWNLOAD NOW!


Book Synopsis A Base Drag Reduction Experiment on the X-33 Linear Aerospike SR-71 Experiment (LASRE) Flight Program by : Stephen A. Whitmore

Download or read book A Base Drag Reduction Experiment on the X-33 Linear Aerospike SR-71 Experiment (LASRE) Flight Program written by Stephen A. Whitmore and published by . This book was released on 1999 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Scientific and Technical Aerospace Reports

Download Scientific and Technical Aerospace Reports PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 702 pages
Book Rating : 4.:/5 (31 download)

DOWNLOAD NOW!


Book Synopsis Scientific and Technical Aerospace Reports by :

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

A Real-time Method for Estimating Viscous Forebody Drag Coefficients

Download A Real-time Method for Estimating Viscous Forebody Drag Coefficients PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 36 pages
Book Rating : 4.:/5 (317 download)

DOWNLOAD NOW!


Book Synopsis A Real-time Method for Estimating Viscous Forebody Drag Coefficients by : Stephen A. Whitmore

Download or read book A Real-time Method for Estimating Viscous Forebody Drag Coefficients written by Stephen A. Whitmore and published by . This book was released on 2000 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper develops a real-time method based on the law of the wake for estimating forebody skin-friction coefficients. The incompressible law-of-the-wake equations are numerically integrated across the boundary layer depth to develop an engineering model that relates longitudinally averaged skin-friction coefficients to local boundary layer thickness. Solutions applicable to smooth surfaces with pressure gradients and rough surfaces with negligible pressure gradients are presented. Model accuracy is evaluated by comparing model predictions with previously measured flight data. This integral law procedure is beneficial in that skin-friction coefficients can be indirectly evaluated in real-time using a single boundary layer height measurement. In this concept a reference pitot probe is inserted into the flow, well above the anticipated maximum thickness of the local boundary layer. Another probe is servomechanism-driven and floats within the boundary layer. A controller regulates the position of the floating probe. The measured servomechanism of this second probe provides an indirect measurement of both local and longitudinally averaged skin friction. Simulation results showing the performance of the control law for a noisy boundary layer are then presented.

NASA Tech Briefs

Download NASA Tech Briefs PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 1004 pages
Book Rating : 4.:/5 (319 download)

DOWNLOAD NOW!


Book Synopsis NASA Tech Briefs by :

Download or read book NASA Tech Briefs written by and published by . This book was released on 1999 with total page 1004 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Viscous Drag Reduction

Download Viscous Drag Reduction PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 500 pages
Book Rating : 4.:/5 (122 download)

DOWNLOAD NOW!


Book Synopsis Viscous Drag Reduction by : C. Sinclair Wells

Download or read book Viscous Drag Reduction written by C. Sinclair Wells and published by . This book was released on 1969 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Experimental Investigation of the Effects of Viscosity on the Drag of Bodies of Revolution at a Mach Number of 1.5

Download Experimental Investigation of the Effects of Viscosity on the Drag of Bodies of Revolution at a Mach Number of 1.5 PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 92 pages
Book Rating : 4.3/5 (126 download)

DOWNLOAD NOW!


Book Synopsis Experimental Investigation of the Effects of Viscosity on the Drag of Bodies of Revolution at a Mach Number of 1.5 by : Dean R. Chapman

Download or read book Experimental Investigation of the Effects of Viscosity on the Drag of Bodies of Revolution at a Mach Number of 1.5 written by Dean R. Chapman and published by . This book was released on 1947 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summary: Tests were conducted to determine the effects of viscosity on the drag and base pressure characteristics of various bodies of revolution at a Mach number of 1.5. The models were tested both with smooth surfaces and with roughness added to evaluate the effects of Reynolds number for both laminar and turbulent boundary layers. The principal geometric variables investigated were after-body shape and length-diameter ratio. For most models, force tests and base pressure measurements were made over a range of Reynolds numbers, based on model length, from 0.6 million to 5.0 millions. Schlieren photographs were used to analyze the effects of viscosity on flow separation and shock-wave configuration near the base and to verify the condition of the boundary layer as deduced from force tests. The results are discussed and compared with theoretical calculations.

Drag Reduction

Download Drag Reduction PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 116 pages
Book Rating : 4.3/5 (97 download)

DOWNLOAD NOW!


Book Synopsis Drag Reduction by : American Institute of Chemical Engineers

Download or read book Drag Reduction written by American Institute of Chemical Engineers and published by . This book was released on 1971 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains

Download The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 354044419X
Total Pages : 534 pages
Book Rating : 4.5/5 (44 download)

DOWNLOAD NOW!


Book Synopsis The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains by : Rose McCallen

Download or read book The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains written by Rose McCallen and published by Springer Science & Business Media. This book was released on 2013-07-30 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is our pleasure to present these proceedings from the United Engineering Foundation Conference on The Aerodynamics of Heavy Vehicles: Trucks, Buses and Trains held December 2-6, 2002, in Monterey, California. This Department of Energy, United Engineering Foundation, and industry sponsored conference brought together 90 leading engineering researchers from around the world to discuss the aerodynamic drag of heavy vehicles. Participants from national labs, academia, and industry, including truck manufacturers, discussed how computer simulation and experimental techniques could be used to design more fuel efficient trucks, buses, and trains. Conference topics included 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 the Department of Energy sponsored and other wind tunnel experiments. Advanced experimental techniques including three-dimensional particle image velocimetry were presented, along with their use in evaluating drag reduction devices. We would like to thank the UEF conference organizers for their dedication and quick response to sudden deadlines. In addition, we would like to thank all session chairs, the scientific advisory committee, authors, and reviewers for their many hours of dedicated effort that contributed to a successful conference and resulted in this document of the conference proceedings. We also gratefully acknowledge the support received from the United Engineering Foundation, the US Department of Energy, Lawrence Livermore National Laboratory, Volvo Trucks America, International Truck and Engine Corporation, and Freightliner LLC.

Mitigation of Hydrodynamic Resistance

Download Mitigation of Hydrodynamic Resistance PDF Online Free

Author :
Publisher : World Scientific
ISBN 13 : 9814612278
Total Pages : 164 pages
Book Rating : 4.8/5 (146 download)

DOWNLOAD NOW!


Book Synopsis Mitigation of Hydrodynamic Resistance by : Marc Perlin

Download or read book Mitigation of Hydrodynamic Resistance written by Marc Perlin and published by World Scientific. This book was released on 2014-11-18 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text presents the state of the art in friction drag/resistance reduction technologies for BODIES and crafts operating in liquids at and beneath the free surface. It is useful for professionals with backgrounds in advanced fluid dynamics as well as by academics teaching introductory graduate courses in this area. Active control of resistance will include a discussion of friction reduction, for example through the injection of gas that can form air layers and polymers that initially reside adjacent to the hull, including the use of partial and super cavities. The book discusses passive resistance control achieved through changes in the overall hull shape and appendages, including the application of lifting bodies, bulbous bows, and stern flaps. It also addresses passive reduction of skin friction through the application of hull coatings and other elements of hull husbandry. Contents:IntroductionActive Techniques:Modification of Drag by Polymer InjectionFriction Drag Reduction by Bubble/Gas InjectionTransition from BDR and Air Layer Drag ReductionFriction Drag Reduction by Partial Air Cavities or PCDRPassive Techniques:Drag Reduction by Super and Partial CavitiesSuper-Hydrophobic Surfaces and CoatingsPassive Resistance-Mitigation by Appendages: Bulbous Bows, Stern Flaps and Wedges, and Lifting Bodies Readership: Professionals, academics, researchers, and graduate students in ocean engineering, mechanical engineering, fluid mechanics and tribology. Keywords:Drag Reduction;Air Layers;Air Cavities;Polymer Injection;Bubble/Gas Injection;Hydrophobic Surfaces;Passive Drag Mitigation

AIAA Aerospace Sciences Meeting and Exhibit, 42nd

Download AIAA Aerospace Sciences Meeting and Exhibit, 42nd PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 532 pages
Book Rating : 4.0/5 ( download)

DOWNLOAD NOW!


Book Synopsis AIAA Aerospace Sciences Meeting and Exhibit, 42nd by :

Download or read book AIAA Aerospace Sciences Meeting and Exhibit, 42nd written by and published by . This book was released on 2004 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The International Vehicle Aerodynamics Conference

Download The International Vehicle Aerodynamics Conference PDF Online Free

Author :
Publisher : Woodhead Publishing
ISBN 13 : 0081002459
Total Pages : 297 pages
Book Rating : 4.0/5 (81 download)

DOWNLOAD NOW!


Book Synopsis The International Vehicle Aerodynamics Conference by : IMechE

Download or read book The International Vehicle Aerodynamics Conference written by IMechE and published by Woodhead Publishing. This book was released on 2014-11-12 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamics has never been more central to the development of cars, commercial vehicles, motorbikes, trains and human powered vehicles, driven by the need for efficiency: reducing carbon dioxide emissions, reducing fuel consumption, increasing range and alleviating problems associated with traffic congestion. Reducing vehicle weight makes it more challenging to ensure that they are stable and handle well over a wide range of environmental conditions. Lighter structures are also more vulnerable to aerodynamically induced vibration. Alongside this, customers demand an environment that is quiet, comfortable and maintains their vision of the world around them in all weathers. These aims must be met by designing vehicles that engage customers emotionally, promoting the brand values of manufacturers and operators. This can only be done by collaboration between designers and aerodynamicists. Examine the latest developments in vehicle aerodynamic development Explore opportunities to network and share experiences around different areas Focus on future challenges and the engineering knowledge and technology required to resolve them Discuss other areas of development including handling and stability, tyre aerodynamics and modelling, aeroacoustics and fluid structure interaction

Drag Reduction

Download Drag Reduction PDF Online Free

Author :
Publisher : Bhra Fluid Engineering
ISBN 13 :
Total Pages : 378 pages
Book Rating : 4.F/5 ( download)

DOWNLOAD NOW!


Book Synopsis Drag Reduction by : Herbert Simon Stephens

Download or read book Drag Reduction written by Herbert Simon Stephens and published by Bhra Fluid Engineering. This book was released on 1977 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Applied Computational Aerodynamics

Download Applied Computational Aerodynamics PDF Online Free

Author :
Publisher : AIAA
ISBN 13 : 9781600863790
Total Pages : 970 pages
Book Rating : 4.8/5 (637 download)

DOWNLOAD NOW!


Book Synopsis Applied Computational Aerodynamics by : P. A. Henne

Download or read book Applied Computational Aerodynamics written by P. A. Henne and published by AIAA. This book was released on 1990 with total page 970 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Fairing Well

Download Fairing Well PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 174 pages
Book Rating : 4.:/5 (318 download)

DOWNLOAD NOW!


Book Synopsis Fairing Well by : Christian Gelzer

Download or read book Fairing Well written by Christian Gelzer and published by . This book was released on 2011 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: