Download or read book Transitional Boundary Layers in Aeronautics written by R. A. W. M. Henkes and published by North Holland. This book was released on 1996 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paperback. The book contains the proceedings of the Colloquium Transitional Boundary Layers in Aeroautics, as organized by the Royal Netherlands Academy of Arts and Sciences on 6-8 December 1995 in Amsterdam.In the external aerodynamics of aircraft, the thin boundary layer along the surface plays an important role. To a large extent, the boundary layer determines the drag of the aircraft. A better knowledge of the laminar-turbulent transition process within the boundary layer may provide technical possibilities for transition control. In this way transition can be postponed, leading to a reduction of the total drag and consequently of the fuel consumption. It is generally recognized that transition belongs to the most difficult problems in fuel mechanics. Fourteen invited papers give an overview of the state-of-the-art of transition phenomena in boundary layers along aircraft surfaces. The emphasis is on the scientific aspects of transition, but resea

Download or read book Analysis of Boundary layer Transition on X 15 2 Research Airplane written by Albert L. Braslow and published by . This book was released on 1966 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Final Report on Three dimensional Structure of Transitional Boundary Layers written by William S. Saric and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Elements of Transitional Boundary Layer Flowlements written by Robert Edward Mayle and published by Logos Verlag Berlin GmbH. This book was released on 2018-09-15 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Second Enhanced Edition Suitable for advanced-level courses or an independent study in fluid mechanics, this text by an expert in the field provides the basic aspects of laminar-to-turbulent flow transition in boundary layers. Logically organized into three major parts, the book covers pre- and post-transitional flow, transitional flow, and several advanced topics in periodically disturbed transitional flow. Some of the subjects covered within the book include high-frequency unsteady laminar flow, turbulent flow, natural transition, bypass transition, turbulent spot theory, turbulent spot kinematics and production, correlations for the onset and rate of transition, global and conditional averaging, transitional flow models, wakeinduced transition, multimode transition, and separated-flow transition. Containing some 202 figures (all drawn by the author), 28 tables, 12 appendices, a supplement on tensors, and an extensive bibliography, the 415 page book provides a wealth of data and information about the subject.

Download or read book Recent Developments in Boundary Layer Transition Research written by United States. National Aeronautics and Space Administration. Transition Study Group and published by . This book was released on 1975 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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:

Download or read book The Boundary layer Transition Characteristics of Two Bodies of Revolution a Flat Plate and an Unswept Wing in a Low turbulence Wind Tunnel written by Frederick W. Boltz and published by . This book was released on 1960 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Boundary Layer Transition at Supersonic Speeds written by E. R. Van Driest and published by . This book was released on 1961 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments carried out in the 12-inch supersonic wind tunnel to investigate the effect of three dimensional roughness elements (spheres) on boundary-layer transition on a 10-degree (apex angle) cone without heat transfer are described. The local Mach number for these tests was 2.71. The data show clearly that the minimum (effective) size of trip required to bring transition to its lowest Reynolds number varies power of the distance from the apex of the cone to the trip. Use of available data at other Mach numbers indicates that the Mach number influence for effective tripping is taken into account by a simple expression. Some remarks concerning the roughness variation for transition on a blunt body are made. Finally, a general criterion is introduced which gives insight to the transition phenomenon and anticipates effects of external and internal disturbances, Mach number transfer.

Download or read book Characteristics of Mach 10 Transitional and Turbulent Boundary Layers written by Ralph D. Watson and published by . This book was released on 1978 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Specific Types of Surface Roughness on Boundary layer Transition written by Laurence K. Loftin and published by . This book was released on 1946 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summary: Tests were conducted with two typical low-drag airfoils of 90-inch chord to determine the effects of surface projections, grooves, and sanding scratches on boundary-layer transition. The Reynolds number at which a spanwise row of cylindrical projections would cause premature transition was determined for a range of Reynolds number from approximately 3 x 106 to 10 x 106. Data were obtained for projections of various sizes and chordwise locations on both low-drag airfoils. The results were analyzed on the assumption that the critical airfoil Reynolds number for a given projection was a function only of the local-flow conditions around the projection. This assumption neglected possible effects of tunnel turbulence, pressure gradient, boundary-layer Reynolds number, and the original extent of the laminar flow. The data correlated on the basis of this assumption within a range of critical airfoil Reynolds number of ±0.5 x 106 and within a range of projection height of ±0.002 inch. The tests of surface grooves and sanding scratches indicated that, for the range of Reynolds number investigated, the laminar boundary layer was much less sensitive to surface grooves and sanding scratches than to projections above the surface.

Download or read book Flight Investigation of Boundary layer Transition and Profile Drag of an Experimental Low drag Wing Installed on a Fighter type Airplane written by John A. Zalovcik and published by . This book was released on 1945 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: A boundary-layer-transition and profile-drag investigation was conducted in flight by the National Advisory Committee for Aeronautics on an experimental low-drag wing installed on a P-47 airplane designated the XP-47F and supplied by the Army Air Forces. The wing incorporates airfoil section that vary from an NACA 66(215)-1(16.5), a = 1.0 at the plane of symmetry to an NACA 67(115)-213, a = 0.7 at the tip. The surface of the wing as constructed was found to have such a degree of waviness that it had to be refinished in order to obtain the performance generally expected of low-drag airfoils. Measurements were made at a section outside the propeller slipstream with smooth and with standard camouflage surfaces and on the upper surface of a section in the propeller slipstream with the surface smoothed. Tests were made in normal flight - that is, in level flight and in shallow dives - at indicated airspeeds ranging from about 150 to 300 miles per hour and in steady turns at 300 miles per hour with normal acceleration from 2g to 4g. These speed and acceleration limits were imposed by structural considerations. The tests in normal flight covered a range of section lift coefficient from about 0.58 to 0.15, of Reynolds number from about 9 x 106 to 18 x 106, and of Mach number from about 0.27 to 0.53. In the tests in turns at 300 miles per hour, the range of section lift coefficient was extended to 0.63.

Download or read book Shock Wave Boundary Layer Interactions written by Holger Babinsky and published by Cambridge University Press. This book was released on 2011-09-12 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock wave-boundary-layer interaction (SBLI) is a fundamental phenomenon in gas dynamics that is observed in many practical situations, ranging from transonic aircraft wings to hypersonic vehicles and engines. SBLIs have the potential to pose serious problems in a flowfield; hence they often prove to be a critical - or even design limiting - issue for many aerospace applications. This is the first book devoted solely to a comprehensive, state-of-the-art explanation of this phenomenon. It includes a description of the basic fluid mechanics of SBLIs plus contributions from leading international experts who share their insight into their physics and the impact they have in practical flow situations. This book is for practitioners and graduate students in aerodynamics who wish to familiarize themselves with all aspects of SBLI flows. It is a valuable resource for specialists because it compiles experimental, computational and theoretical knowledge in one place.

Download or read book Two Techniques for Detecting Boundary layer Transition in Flight at Supersonic Speeds and at Altitudes Above 20 000 Feet written by John G. McTigue and published by . This book was released on 1959 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Solution of the Equations for Compressible Laminar Transitional and Turbulent Boundary Layers and Comparisons with Experimental Data written by Julius E. Harris and published by . This book was released on 1971 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: A numerical method for solving the equations for laminar, transitional, and turbulent compressible boundary layers for either planar or axisymmetric flows is presented. The fully developed turbulent region is treated by replacing the Reynolds stress terms with an eddy viscosity model. The mean properties of the transitional boundary layer are calculated by multiplying the eddy viscosity by an intermittency function based on the statistical production and growth of the turbulent spots. A specifiable turbulent Prandtl number relates the turbulent flux of heat to the eddy viscosity. A three-point implicit finite-difference scheme is used to solve the system of equations. The momentum and energy equations are solved simultaneously without iteration. Numerous test cases are compared with experimental data for supersonic and hypersonic flows; these cases include flows with both favorable and mildly unfavorable pressure gradient histories, mass flux at the wall, and traverse curvature.

Download or read book A Nonlinear Theory for Predicting the Effects of Unsteady Laminar Turbulent Or Transitional Boundary Layers on the Attenuation of Shock Waves in a Shock Tube with Experimental Comparison written by Robert L. Trimpi and published by . This book was released on 1958 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: The linearized attenuation theory of NACA Technical Note 3375 is modified in the following manner: (a) an unsteady compressible local skin-friction coefficient is employed rather than the equivalent steady-flow incompressible coefficient; (b) a nonlinear approach is used to permit application of the theory to large attenuations; and (c) transition effects are considered. Curves are presented for predicting attenuation for shock pressure ratios up to 20 and a range of shock-tube Reynolds numbers. Comparison of theory and experimental data for shock wave strengths between 1.5 and 10 over a wide range of Reynolds numbers shows good agreement with the nonlinear theory evaluated for a transition Reynolds nuniber of 2.5 million.

Download or read book Linear Stability Theory and Three Dimensional Boundary Layer Transition written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-20 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The viewgraphs and discussion of linear stability theory and three dimensional boundary layer transition are provided. The ability to predict, using analytical tools, the location of boundary layer transition over aircraft-type configurations is of great importance to designers interested in laminar flow control (LFC). The e(sup N) method has proven to be fairly effective in predicting, in a consistent manner, the location of the onset of transition for simple geometries in low disturbance environments. This method provides a correlation between the most amplified single normal mode and the experimental location of the onset of transition. Studies indicate that values of N between 8 and 10 correlate well with the onset of transition. For most previous calculations, the mean flows were restricted to two-dimensional or axisymmetric cases, or have employed simple three-dimensional mean flows (e.g., rotating disk, infinite swept wing, or tapered swept wing with straight isobars). Unfortunately, for flows over general wing configurations, and for nearly all flows over fuselage-type bodies at incidence, the analysis of fully three-dimensional flow fields is required. Results obtained for the linear stability of fully three-dimensional boundary layers formed over both wing and fuselage-type geometries, and for both high and low speed flows are discussed. When possible, transition estimates form the e(sup N) method are compared to experimentally determined locations. The stability calculations are made using a modified version of the linear stability code COSAL. Mean flows were computed using both Navier Stokes and boundary-layer codes. Spall, Robert E. and Malik, Mujeeb R. Unspecified Center ...

Download or read book Stability and Transition in Shear Flows written by Peter J. Schmid and published by Springer Science & Business Media. This book was released on 2000-12-28 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed look at some of the more modern issues of hydrodynamic stability, including transient growth, eigenvalue spectra, secondary instability. It presents analytical results and numerical simulations, linear and selected nonlinear stability methods. By including classical results as well as recent developments in the field of hydrodynamic stability and transition, the book can be used as a textbook for an introductory, graduate-level course in stability theory or for a special-topics fluids course. It is equally of value as a reference for researchers in the field of hydrodynamic stability theory or with an interest in recent developments in fluid dynamics. Stability theory has seen a rapid development over the past decade, this book includes such new developments as direct numerical simulations of transition to turbulence and linear analysis based on the initial-value problem.