Free Flight Hypersonic Heat Transfer and Boundary Layer Transition Studies
Title | Free Flight Hypersonic Heat Transfer and Boundary Layer Transition Studies PDF eBook |
Author | James E. Brunk |
Publisher | |
Pages | 168 |
Release | 1961 |
Genre | Aerodynamic heating |
ISBN |
Two HTV-1 Hypersonic Test Vehicles, Rounds A-40 and A-41, were flown at Holloman AFB in October 1959, with blunted and sharp 20 degree half angle nose cones, respectively. Round A-40 also incorporated nose cone incidence and a pitch disturber rocket. A maximum flight velociety of 5800 feet per second was attained, corresponding to a local shap cone Mach number and unit Reynolds number of 3.4 and 50 x 10(6) per foot respectively. Fligh dynamics data for the second stage of Round A-40 were obtained from analyses of the vector angle of attack history. The measured maximum trim angle of attack (1.5 degrees) agreed closely with the predicted trim based on an elastic structure and a nose cone incidence of 0.36 degrees. Surface temperatures and aerodynamic heating rates were obtained for one station and three radial positions on the conical portion of the blunted nose cone (Round A-40) and at 3 stations on each of the two longitudinal rays on the sharp cone (Round A-41). In addition, the temperature and heating rates were determined on the cylindrical portion of the Round A-41 payload and on the base of on Stage II fin for both vehicles. The maximum heating rate for the sharp cone was about 30 percent greater for the blunt cone as a result of higher local Mach numbers and Reynolds numbers on the sharp cone. Correlation of the blunted cone circumferential heating rates with the measured angle of attack showed that only a small increase in heating rate (less than about 5 percent increase from the zero angle of attack heating rate) occurs on the windward ray for turbulent heating conditions. The measured decrease in Stanton mumber with increasing Reynolds number (running length) for the sharp cone was found to be in close agreement with turbulent flow theory. Boundary layer transition reversal from turbulent to laminar flow was experienced on both the sharp and blunted tip cones. Transition reversal for the sharp cone, which had almost twice the local Mach number of the blunted cone, was found to occur at an enthalpy ratio, hw/hr, 30 percent greater than for the blunted cone. For both cones turbulent flow occurred within the Mach number and enthalpy region for complete stability of two dimensional disturbance as defined by Dunn and Lin. The possible effects of surface roughness in producing the observed transition reversal are discussed.
Advances in Hypersonics
Title | Advances in Hypersonics PDF eBook |
Author | BALLMAN |
Publisher | Springer Science & Business Media |
Pages | 448 |
Release | 2012-12-06 |
Genre | Technology & Engineering |
ISBN | 1461203791 |
These three volumes entitled Advances in Hypersonics contain the Proceedings of the Second and Third Joint US/Europe Short Course in Hypersonics which took place in Colorado Springs and Aachen. The Second Course was organized at the US Air Force Academy, USA in January 1989 and the Third Course at Aachen, Germany in October 1990. The main idea of these Courses was to present to chemists, com puter scientists, engineers, experimentalists, mathematicians, and physicists state of the art lectures in scientific and technical dis ciplines including mathematical modeling, computational methods, and experimental measurements necessary to define the aerothermo dynamic environments for space vehicles such as the US Orbiter or the European Hermes flying at hypersonic speeds. The subjects can be grouped into the following areas: Phys ical environments, configuration requirements, propulsion systems (including airbreathing systems), experimental methods for external and internal flow, theoretical and numerical methods. Since hyper sonic flight requires highly integrated systems, the Short Courses not only aimed to give in-depth analysis of hypersonic research and technology but also tried to broaden the view of attendees to give them the ability to understand the complex problem of hypersonic flight. Most of the participants in the Short Courses prepared a docu ment based on their presentation for reproduction in the three vol umes. Some authors spent considerable time and energy going well beyond their oral presentation to provide a quality assessment of the state of the art in their area of expertise as of 1989 and 1991.
Boundary Layer Transition at Supersonic Speeds
Title | Boundary Layer Transition at Supersonic Speeds PDF eBook |
Author | E. R. Van Driest |
Publisher | |
Pages | 108 |
Release | 1961 |
Genre | Aerodynamics, Supersonic |
ISBN |
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.
A Review of High-speed, Convective, Heat-transfer Computation Methods
Title | A Review of High-speed, Convective, Heat-transfer Computation Methods PDF eBook |
Author | Michael E. Tauber |
Publisher | |
Pages | 44 |
Release | 1989 |
Genre | Aerodynamic heating |
ISBN |
Shock Wave-Boundary-Layer Interactions
Title | Shock Wave-Boundary-Layer Interactions PDF eBook |
Author | Holger Babinsky |
Publisher | Cambridge University Press |
Pages | 481 |
Release | 2011-09-12 |
Genre | Technology & Engineering |
ISBN | 1139498649 |
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.
Boundary Layer Flows
Title | Boundary Layer Flows PDF eBook |
Author | Vallampati Ramachandra Prasad |
Publisher | BoD – Books on Demand |
Pages | 236 |
Release | 2020-01-22 |
Genre | Mathematics |
ISBN | 1839681853 |
Written by experts in the field, this book, "Boundary Layer Flows - Theory, Applications, and Numerical Methods" provides readers with the opportunity to explore its theoretical and experimental studies and their importance to the nonlinear theory of boundary layer flows, the theory of heat and mass transfer, and the dynamics of fluid. With the theory's importance for a wide variety of applications, applied mathematicians, scientists, and engineers - especially those in fluid dynamics - along with engineers of aeronautics, will undoubtedly welcome this authoritative, up-to-date book.
Simplified Method for Determination of Critical Height of Distributed Roughness for Boundary-layer Transition at Mach Numbers from 0 to 5
Title | Simplified Method for Determination of Critical Height of Distributed Roughness for Boundary-layer Transition at Mach Numbers from 0 to 5 PDF eBook |
Author | Albert L. Braslow |
Publisher | |
Pages | 624 |
Release | 1958 |
Genre | Airplanes |
ISBN |
The method has been applied to various types of configurations in several wind-tunnel investigations conducted by the National Advisory Committee for Aeronautics at Mach numbers up to 4, and in all cases the calculated roughness height caused premature boundary-layer transition for the range of test conditions.