Author: Gérard DegrezPublisher:
ISBN:
Category :
Languages : en
Pages : 138
Book Description
Exploratory Experimental Investigation of the Unsteady Aspects of Blunt Fin Induced Shock Wave Turbulent Boundary Layer Interactions
Author: Gérard DegrezAn Experimental Investigation of the Unsteady Behavior of Blunt Fin-Induced Shock Wave Turbulent Boundary Layer Interactions
Author: David S. DollingPublisher:
ISBN:
Category :
Languages : en
Pages : 46
Book Description
An experimental study has been made of blunt fin-induced shock wave turbulent boundary layer interactions. This type of interaction is known to be highly unsteady. The objective of this experiment was to determine the characteristics of the fluctuating surface pressure distribution and the parameters controlling it. Tests have been made using fins of different diameter, D, with incoming turbulent boundary layers varying in thickness, Delta, in the ratio of about 5:1. Measurements have been made on the fin centerline and up to four diameters outboard of it. All tests were made at a Mach number of 2.95 and a unit Reynolds number of 6.3 billion/m, and under approximately adiabatic wall conditions. The measurements show that very high intensity r.m.s. pressure levels occur--up to almost two orders of magnitude above that of the incoming boundary layer. The highest intensities occur on centerline ahead of the fin. Here, the r.m.s. pressure distribution is characterized by three distinct peaks which decrease at different rates with distance outboard. Even four diameters off centerline, the maximum r.m.s. value in the distribution is still an order of magnitude larger than that of the incoming boundary layer. Outboard of the centerline, the r.m.s. pressure level downstream of the freestream shock wave steadily decreases. Within a distance of six to eight diameters it is close to the undisturbed value. With different diameter fins and different boundary layers, the qualitative characteristics are the same. The quantitative results depend on the ratio D/Delta. (Author).
Investigation of the Unsteady Aspects of Blunt Fin Induced Shock Wave Turbulent Boundary Layer Interactions
Author: Gerard DegrezExperimental Investigation of Three-Dimensional Shock Wave Turbulent Boundary Layer Interaction: An Exploratory Study of Blunt Fin-Induced Flows
Author: David S. DollingPublisher:
ISBN:
Category :
Languages : en
Pages : 75
Book Description
An experimental study of three-dimensional (3-D) shock wave turbulent boundary layer interaction has been carried out. Interactions generated by fin models having sharp and hemi-cylindrically blunted leading edges have been studied. The emphasis in this particular study was twofold. First, the influence of incoming turbulent boundary layer thickness delta on the streamwise, spanwise and vertical scaling of the interaction was examined. Turbulent boundary layers varying in thickness from .127 cm (.05 in.) to 2.27 cm (0.89 in.) were used. In addition, a study has been conducted to examine the effects of the ratio D/delta (where D is the blunt fin leading edge diameter) on the interaction properties and scaling. Second, an investigation has been started to examine the unsteady shock wave-boundary layer structure and the resulting high frequency, large amplitude pressure fluctuations which occur ahead of and around the blunt fin leading edge. This is an area which in the past has been largely ignored, yet has important implications, since it is not clear that any mean surface property or flowfield measurements have any real physical significant. To date, measurement techniques and computer software have been developed and exploratory measurements made in the undisturbed turbulent boundary layer and also on the plane of symmetry ahead of the blunt fin.
Experimental Investigation of Unsteady Shock Wave Turbulent Boundary Layer Interactions About a Blunt Fin
Author: Masters Theses in the Pure and Applied Sciences
Author: Wade ShaferPublisher: Springer Science & Business Media
ISBN: 1461337003
Category : Science
Languages : en
Pages : 335
Book Description
Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volume were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 26 (thesis year 1981) a total of 11 ,048 theses titles from 24 Canadian and 21 8 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 26 reports theses submitted in 1981, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.
Experimental Investigation of Unsteady Shock Wave Turbulent Boundary Layer Interactions about a Blunt Fin
Author: Paul J. BarnhartTurbulent Shear-Layer/Shock-Wave Interactions
Author: J. DeleryPublisher: Springer Science & Business Media
ISBN: 3642827705
Category : Science
Languages : en
Pages : 434
Book Description
It was on a proposal of the late Professor Maurice Roy, member of the French Academy of Sciences, that in 1982, the General Assembly of the International Union of Theoretical and Applied Mechanics decided to sponsor a symposium on Turbulent Shear-Layer/Shock-Wave Interactions. This sympo sium might be arranged in Paris -or in its immediate vicinity-during the year 1985. Upon request of Professor Robert Legendre, member of the French Academy of Sciences, the organization of the symposium might be provided by the Office National d'Etudes et de Recherches Aerospatiales (ONERA). The request was very favorably received by Monsieur l'Ingenieur General Andre Auriol, then General Director of ONERA. The subject of interactions between shock-waves and turbulent dissipative layers is of considerable importance for many practical devices and has a wide range of engineering applications. Such phenomena occur almost inevitably in any transonic or supersonic flow and the subject has given rise to an important research effort since the advent of high speed fluid mechanics, more than forty years ago. However, with the coming of age of modern computers and the development of new sophisticated measurement techniques, considerable progress has been made in the field over the past fifteen years. The aim of the symposium was to provide an updated status of the research effort devoted to shear layer/shock-wave interactions and to present the most significant results obtained recently.
Physics of unsteady blunt fin-induced shock wave/turbulent boundary layer interactions
Author: Leon BrusniakPublisher:
ISBN:
Category : Leading edges (Aerodynamics)
Languages : en
Pages : 702
Book Description
An Exploratory Investigation of Sharp Fin - Induced Shock Wave
Author: Scott P. GoodwinPublisher:
ISBN:
Category :
Languages : en
Pages : 156
Book Description
For this thesis an experimental investigation of sharp fin-induced shock/boundary layer interactions was carried out at a Mach number of 2.95, unit Reynolds numbers ranging from 1 to 4 million per inch, boundary layer thicknesses of 0.14 and 0.50 inches, and fin angles of attack between 12 and 22 degrees. Surface pressure and surface flow visualization data were collected. Results showed that high shock strength interactions were qualitatively similar to those at low shock strengths. When compared to two-dimensional test results, the present three-dimensional data were seen to have a similar dependence on Reynolds number but a different sort of dependence on shock strength. The data were also seen to possess conical similarity. As was the case at lower shock strengths, the interactions could be scaled using unit Reynolds number, boundary layer thickness, and normal Mach number. The appearance of the feature termed secondary separation was noted to depend on boundary layer thickness. Competing feature and turbulence scales were hypothesized to produce this dependence.