Download or read book Research on Hypersonic Flow of Blunt Delta Wings Part Ii Gap Effects of a Blunt Slab Delta Wing at Moderate Supersonic and Hypersonic Speeds written by Bernard Mazelsky and published by . This book was released on 1968 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: It was found that the maximum lift to drag ratio of a flat delta wing at moderate supersonic and hypersonic speeds can be increased appreciably by letting a small amount of air pass through narrow gaps located at proper places on the wing. The increase in (L/D)max obtained from such a wing experiment varies from 5% to 17% at different speeds. Six gap configurations were tested at four different free stream Mach numbers, M = 4, 4.5, 5 and 8. Reynold's number was kept constant at Re/in = 300,000 and 700,000. Both the lift and drag of the wing were reduced due to the presence of gaps. Since the decrease in drag is greater than that of lift, L/D is thus increased. The reduction in lift is due to the loss of momentum and the increase of pressure in the induced separation region on the leeward side of the wing; the reduction in drag is due to the decrease in skin-friction caused by gap effects. (Author).
Download or read book Research on Hypersonic Flow of Blunt Delta Wings Part Iii Gap Effects of a Blunt Slab Delta Wing at Moderate Supersonic and Hypersonic Speeds written by Bernard Mazelsky and published by . This book was released on 1968 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation of the effect of air ejecting from the windward side to the leeward side through gaps located on a delta wing on the aerodynamic performance was made at hypersonic speeds, M = 6 and 10, and at three Reynolds numbers, Re/ft = 1,500,000, 1,600,000 and 3,800,000. The tested data and the oil flow photographs indicate that the gap effect has a negligible influence on the lift and drag of the wing at the tested Mach numbers and Reynolds numbers. The model used in these tests was the same as that used for the previous experiment (Part II) wherein the gap width varied from 0.015 inch to 0.045 inch. In addition to the measurement of lift and drag, velocity profiles, surface pressures and base pressures were also measured in the present experiment. (Author).
Download or read book OAR Cumulative Index of Research Results written by and published by . This book was released on 1967 with total page 1264 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 1972 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Research on Hypersonic Flow of Blunt Delta Wings Part I Theoretical and Experimental Study of a 70 degree Blunt Delta Wing for Low Angles of Attack at Supersonic and Hypersonic Speeds written by Bernard Mazelsky and published by . This book was released on 1967 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The object of the present analysis is to investigate the high-speed aerodynamic properties of a blunt delta wing at low angles of attack where the maximum lift to drag ratio occurs. Oguchi's solution of hypersonic flow over a blunt leading edge flat plate at zero incidence is extended to three dimensional delta wings at angle of attack. The shock wave shapes and pressure distributions were obtained by employing the oblique shock relations at the windward sides of the Prandtl-Meyer equations at the leeward side of the wing. The total lift and drag of the wing due to pressure and skin friction were computed by numerical integration using the IBM 7094 computer. The present calculated aerodynamic forces generally agree with the experimental data at the high supersonic Mach numbers (M approx.> or = 4) and lower thickness ratio of the wing which is a 70-degree swept slab sided delta wing with a cylindrical leading edge. (Author).
Download or read book OAR Index of Research Results written by United States. Air Force. Office of Aerospace Research and published by . This book was released on 1967 with total page 1262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Development Reports written by and published by . This book was released on 1968 with total page 1152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Blunt Slab Delta Wing at Hypersonic Speeds and Angles of Attack written by Gerald L. Burke and published by . This book was released on 1972 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents information obtained during an extensive AFFDL study of the flow field about blunt, slab delta wings. Data taken during the study include surface heat transfer and pressure, pitot surveys, oil flows, schlierens, shadowgraphs, and vapor screens. The main lesson of the study is the three-dimensionality of the flow field in addition to the documented effects of inflow and outflow. The most unexpected phenomenon was the appearance of a hot streak on the lower surface off the center line. It is proposed that this region of higher heating is due to a slip line originating at the point of inflection in the shock wave between the bow shock and the leading edge shock. This proposition is supported by pitot pressure surveys and surface pressure distributions. Other qualitative features of the flow field which are presented include the movement of the leading edge stagnation line onto the lower surface. The relative entropy levels of the flow field and the use of vapor screens in hypersonic tunnels are discussed. (Author).
Download or read book U S Government Research and Development Reports written by and published by . This book was released on 1968 with total page 1150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research on Hypersonic Flow of Blunt Delta Wings written by and published by . This book was released on 1967 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Scientific and Industrial Reports written by and published by . This book was released on 1968 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research on Hypersonic Flow of Blunt Delta Wings at Low Angles of Attack written by and published by . This book was released on 1966 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Hypersonic Flow Past Blunted Flat Delta Wings written by Arnold Polak and published by . This book was released on 1970 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow of a perfect gas over the slab portion of a blunted delta wing flying at hypersonic speeds is studied. A set of approximate equations is derived and a solution - for an inviscid flow - is obtained. Using this solution as a representation for the inviscid flow problem, a formulation to the laminar boundary-layer equations is presented; one which is applicable to the flow field's azimuthal planes where the crossflow gradients are not too large. Numerical solutions to these boundary-layer equations have been obtained; however, these are restricted to the azimuthal planes and near to the leading edges. The results indicate the presence of a dividing surface streamline since a numerical solution could not be obtained near the centerplane of the wing, where the crossflow velocity is large. (Author).
Download or read book Government Reports Announcements written by and published by . This book was released on 1967 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research and Development Reports Index written by and published by . This book was released on 1968 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hypersonic Flow of Blunt Delta Wings at Low Angles of Attack I Shock Wave Shape and Surface Pressure Distribution written by Bernard Mazelsky and published by . This book was released on 1966 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report covers a portion of a research program on the aerodynamic characteristics of a cylindrical-leading-edge 70 degrees swept delta wing at high supersonic and moderate hypersonic Mach numbers, and for small values of angle of attack. Prior to the calculation of the lift and drag characteristics of the wing, a semi-empirical method was developed to predict the shock wave shape surrounding the wing as well as the corresponding pressure distribution on the wing surface. The theoretical shock shape and pressure distribution results are compared with experiments available from the open literature as well as with experimental pressure distributions obtained in the present program on the tip portion of a blunt 70 degrees swept delta wing. Within the range of applicability of the semi-empirical method, the predicted shock wave shapes are in good agreement with experiment. The calculated pressure distributions agree quite well with experiment, provided the angle of attack is below 15 degrees and the Mach number is above M = 3.0.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 1652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
