Download or read book Flow visualization of Three dimensional Boundary layer Separation on Bodies of Revolution at Incidence written by Taeyoung Han and published by . This book was released on 1977 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface streamline patterns on three bodies of revolution, namely a spheroid, a low-drag body and a hemisphere-hemispheroid combination body, have been examined at several angles of attack. Most of the tests were performed at low Reynolds numbers in a hydraulic flume using colored dye to make the surface flow visible. A limited number of experiments was also carried out in a wind tunnel, using wool tufts, to study the influence of Reynolds number and turbulent separation. The study has verified some of the important qualitative features of three-dimensional separation criteria proposed earlier by Maskell, Lighthill, Wang and others. The observed locations of laminar separation lines on a spheroid at various incidences have been compared with the numerical boundary-layer solutions of Wang, and it is suggested that the quantitative differences may be attributed to the significant viscous-inviscid interaction, especially at large incidences. (Author).
Download or read book Three Dimensional Boundary Layers on Bodies of Revolution at Incidence written by V. C. Patel and published by . This book was released on 1978 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the objectives and accomplishments of an experimental and theoretical investigation of the boundary layer development on bodies of revolution at incidence. The results of the flow visualization studies in laminar flow, detailed measurements in a turbulent boundary layer, and calculations of laminar as well as turbulent boundary layers using two different numerical schemes and turbulence models are reviewed to emphasize the important characteristics of separation in three dimensions.
Download or read book Flow Visualisation of Three Dimensional Boundray Layer Separation on Bodies of Revolution at Incidence written by Taeyoung Han and published by . This book was released on 1977 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Boundary Layers and Separation Patterns on a Body of Revolution at Incidence written by H. U. Meier and published by . This book was released on 1982 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed measurements in three-dimensional boundary layers and separated flow fields, developing on a prolate spheroid, are presented. The discussion is concentrated on the possible topological structure of separation patterns resulting from laminar or turbulent boundary layer flows. A hypothesis about the transition from an unsteady two-dimensional axisymmetric flow separation into a steady three-dimensional vortex flow is established. (Author).
Download or read book Calculation of Three dimensional Boundary Layers on Bodies at Incidence written by V. C. Patel and published by . This book was released on 1982 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three-dimensional thin boundary-layer equations for laminar and turbulent flows are solved by two different numerical schemes. The methods are applied to the flow over bodies of revolution at incidence and the results are compared with the available experimental data in order to study the range of validity of the classical boundary-layer approximations in regions of increasing circumferential gradients and flow reversal associated with the early stages of a free-vortex type of separation. Comparison with the DFVLR 6:1 spheroid data of Meier et al and the 4:1 combination-body data of Ramaprian, Patel and Choi indicate that the methods perform well in regions where the boundary layer remains thin but the predictions deteriorate as the boundary layer thickens. The results point out the need for the development of methods of handle thick boundary layers and viscous-inviscid interactions. (Author).
Download or read book Topological Analysis of Computed Three dimensional Viscous Flow Fields written by and published by . This book was released on 1982 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies on Three Dimensional Boundary Layers on Bodies of Revolution II Three Dimensional Laminar Boundary Layers and the OK of Accessibility written by Tuncer Cebeci and published by . This book was released on 1980 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation is carried out into the structure of the laminar boundary layer originating from the forward stagnation point of a prolate spheroid at incidence in a uniform stream, assuming that the external velocity distribution is given by attached potential theory. The principal new results of the study are: (1) A new transformation of the body coordinates is devised which facilitates the computation of the solution near the nose, (2) Two variations of the standard box method of solving the equations are devised to enable solutions to be computed in regions of cross-flow reversal, (3) Whereas in two dimensional flows the effect of the boundary layer approaching separation on the external flow may be represented by a blowing velocity, in the present study we find that this is only true near the windward line of symmetry, (4) The boundary layer over the whole of the spheroid cannot be computed in an integration from the forward stagnation point. (5) For alpha> or = 15 deg the accessible region on the leeward side of the ok is largely determined by the external streamline through the ok.
Download or read book Three Dimensional Laminar Boundary Layer Over Body of Revolution at Incidence Part VII The Extremely High Incidence Case written by K. C. Wang and published by . This book was released on 1973 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report presents results of exact, full three-dimensional solutions of the incompressible laminar boundary layer over a prolate spheroid at an extremely high incidence. In contrast to the high incidence (30 degrees) case recently reported, this extremely high incidence (45 degrees) problem is characterized by features reflecting the predominance of the circumferential flow over the meridional flow and, more importantly, by a closed, rather than an open, separation pattern. These features include much larger circumferential skin friction than meridional skin friction and that the limiting streamlines are more closely oriented along the parallels. (Author).
Download or read book Three Dimensional Turbulent Boundary Layer on a Body of Revolution at Incidence written by V. C. Patel and published by . This book was released on 1983 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental and theoretical study of three-dimensional boundary layers on bodies of revolution at incidence was conducted during the period May 1980-July 1983. This final report summarizes the technical accomplishments. Reference is made to previous reports and papers resulting from the study and some recent experimental results on the boundary layer in the plane of symmetry and the vortex formation region are presented. One of the primary objectives of this study was to develop instrumentation for the measurement of the mean flow and the Reynolds stresses in three-dimensional turbulent boundary layers, and to use these to supplement the mean-flow measurements made earlier by Ramaprian, Patel and Choi on the combination body at an incidence of 15 degrees.
Download or read book Preliminary Surveys of the Three Dimensional Boundary Layer on a Yawed Spinning Body of Revolution written by Walter B. Sturek and published by . This book was released on 1975 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental measurements of the three dimensional boundary layer on a yawed, spinning tangent-ogive-cylinder model in supersonic flow are reported. The measurements were made using a flattened total head probe at one axial station near the base of the model for 10 azimuthal stations about the circumference. The test conditions were: M = 3, angle of attack = 4 deg, omega = 0 and 10,000 RPM. The trends observed in comparing measurements with and without the model spinning were: (1) the boundary layer is more thick and less full where surface spin opposes the crossflow velocity; and (2) the boundary layer is less thick and more full where surface spin is in the same direction as the crossflow velocity. (Author).
Download or read book The Structure of Three dimensional Separated Flows in Obstacle boundary Layer Interactions written by Raymond Sedney and published by . This book was released on 1975 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject is investigated with flow visualization techniques; the turbulent boundary layer on the wall of a continuous supersonic wind tunnel is used. Sizeable separated flow regions can be studied since the wall width is 38cm and the boundary layer is typically 2.5cm thick. The large scale of the experiment is required to resolve the fine details of the flow structure. The flow visualization techniques are discussed. The structure of the separated flow upstream of the obstacle is seen to change with relatively small changes in Reynolds number R; the number of vortices varies from 6 to 4 to 2 as R changes. Data are presented for large and small protuberances, but the latter are emphasized.
Download or read book Three Dimensional Laminar Boundary Layer Over Body of Revolution at Incidence Part VI General Methods and Results of the Case of High Incidence written by K. C. Wang and published by . This book was released on 1973 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report presents general methods for calculating three-dimensional laminar boundary layers over inclined blunt bodies (not necessarily bodies of revolution). Complete incompressible results for a prolate spheroid at 30 degrees incidence are presented, and the computational procedures are described. The rule of the zone of dependence was observed. The results display for the first time the boundary layer structure over a non-spherical and non-conical blunt body in all details, and confirm the open-type of separation proposed earlier. (Author).
Download or read book Boundary Layer Separation Due to Weak and Strong Viscous Inviscid Interaction on an Inclined Body of Revolution written by H. U. Meier and published by . This book was released on 1984 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed measurements in three-dimensional boundary layers and separated flow fields, developing on a prolate spheroid and flow visualizations are presented. The discussion is concentrated on the possible topological structure of separation patterns resulting from laminar on turbulent boundary layer flows at different Reynolds numbers. (Author).
Download or read book Three Dimensional Laminar Boundary Layer Over Body of Revolution at Incidence Part V Further Investigation Near the Plane of Symmetry written by Kuo C. Wang and published by . This book was released on 1971 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The previously investigated three-dimensional boundary layer near the plane of symmetry of an inclined spheroid is extended along three directions: wider range of solutions, explanations to questions left unanswered before, and comparisons with experiments. Extended solutions provide more complete trends for incidences from zero to 90 degrees and for thickness ratios ranging from unity for a sphere to nearly zero for a long inclined sylinder. Among these trends is how the separation changes from one type to another and then back again with increasing incidence. Explanations are given for a number of unconventional features; included here is why the lateral derivative of the cross velocity profile reverses. Agreement with Wilson's recent experiments (designed specifically for partial check of the results obtained earlier) enhances the significance of the investigation undertaken.
Download or read book Three Dimensional Laminar Boundary Layer Over Body of Revolution at Incidence Part VIII The Case of Low Incidence Involving Circumferential Flow Reversal written by K. C. Wang and published by . This book was released on 1974 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work concerns an investigation of three-dimensional laminar boundary layer over a blunt body (prolate spheroid) at low incidence and with reversed flow. Results reflecting the general characteristics of such a problem are presented. More significant are the features relating to the circumferential-flow reversal.
Download or read book Computation of Navier Stokes Equations for Three dimensional Flow Separation written by and published by . This book was released on 1989 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
