Download or read book Acoustic Test of a Model Rotor and Tail Rotor written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-06 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic data from a model scale main rotor and tail rotor experiment in the NASA Langley 14 by 22 Foot Subsonic Tunnel are presented for the main rotor and trail rotor in isolation and for the two rotors operating together. Results for the isolated main rotor show the importance of the rotor flapping conditions on mid-frequency noise content. High levels of main rotor retreating side blade-vortex interaction noise are shown to radiate downstream of the model. The isolated tail rotor noise results show the dominance of harmonic noise in the thrusting direction. The occurrence of tail rotor broadband noise is seen by the broadening of the tail rotor harmonics and is attributed to fuselage wake turbulence. The combined main and tail rotor data are presented to show the dominance of each rotor's different noise sources at different directivity locations. Martin, R. M. and Burley, C. L. and Elliott, J. W. Langley Research Center...
Download or read book Acoustic Test of a Model Rotor and Tail Rotor Results for the Isolated Rotors and Combined Configuration written by and published by . This book was released on 1989 with total page 76 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 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Engineering Acoustics written by Gerhard Müller and published by Springer Science & Business Media. This book was released on 2012-11-06 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: This acoustics handbook for mechanical and architectural applications is a translation of the German standard work on the subject. It not only describes the state of art of engineering acoustics but also gives practical help to engineers for solving acoustic problems. It deals with the origin, the transmission and the methods of abatement of air-borne and structure-borne sound of different kinds, from traffic to machinery and flow induced sound.
Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1990 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on with total page 1200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1991 with total page 1644 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1971 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)
Download or read book Aeronautical Engineering A Cumulative Index to a Continuing Bibliography supplement 248 written by and published by . This book was released on 1990 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Special Course on Inverse Methods for Airfoil Design for Aeronautical and Turbomachinery Applications written by and published by . This book was released on 1990 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This lecture series is devoted to major aspects of aerofoil design both for aeronautical and turbomachine application. These include: (1) optimisation of target pressure and velocity distribution. Both direct optimisation resulting from an inverse boundary layer calculation and an iterative optimisation of the loses are presented. (2) aerofoil design by means of inverse methods. This ranges from simple parametric definitions of two- dimensional cross sections to a detailed numerical definition of three dimensional shapes. blade or airfoil designs are normally made in two steps, and the lectures are accordingly grouped into two parts. First, optimisation of target pressure and velocity distributions are discussed taking into account the required performance and the lost mechanisms in the boundary layer. Both direct optimisation resulting from an inverse boundary layer calculation, and an iterative optimisation by minimisation of the losses are presented. It is clear from both procedures that inclusion of off-design operation is one of the greatest difficulties involved in blade or airfoil operation. The second part gives an overview of the numerous inverse blade design methods that have been developed both for turbomachinery and aeronautical applications. This ranges from simple parameter definitions of two-dimensional cross-sections to the full three-dimensional definition of wings and blade channels."--DTIC.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1989 with total page 1372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1992 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications Cumulative Index written by United States. Superintendent of Documents and published by . This book was released on 1976 with total page 1466 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow Environment Study Near the Empennage of a 15 Percent Scale Helicopter Model written by Susan Althoff Gorton and published by . This book was released on 2000 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of advanced rotorcraft configurations has highlighted a need for high-quality experimental data to support the development of flexible and accurate analytical design tools. To provide this type of data, a test program was conducted in the Langley 14- by 22-Foot Subsonic Tunnel to measure the flow near the empennage of a 15-percent scale powered helicopter model with an operating tail fan. Three-component velocity profiles were measured with laser velocimetry (LV) one chord forward of the horizontal tail for four advance ratios to evaluate the effect of the rotor wake impingement on the horizontal tail angle of attack. These velocity data indicate the horizontal tail can experience unsteady angle of attack variations of over 30 degress due to the rotor wake influence. The horizontal tail is most affected by the rotor wake above advance ratios of 0.10. Velocity measurements of the flow on the inlet side of the tail fan were made for a low-speed flight condition using conventional LV techniques. The velocity data show an accelerated flow near the tail fan duct, and vorticity calculations track the passage of main rotor wake vortices through the measurement plane.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1989 with total page 1056 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Memorandum written by and published by . This book was released on 1963 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research and Technology Annual Report written by Earth Resources Laboratory (U.S.) and published by . This book was released on 1987 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
