Download or read book The Shielding of Engine Noise by an Aircraft Wing written by E.G. Broadbent and published by . This book was released on 1970 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimation of the Shielding Effect of the Wing on Aircraft Engine Noise Using the Kirchhoff approximation written by J. J. Tiggelaar and published by . This book was released on 1973 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Database of Inlet and Exhaust Noise Shielding for Wedge shaped Airframe written by Carl H. Gerhold and published by . This book was released on 2001 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experiment to measure the noise shielding of the blended wing body design concept was developed using a simplified wedge-shaped airframe. The experimental study was conducted in the Langley Anechoic Noise Research facility. A wideband, omnidirective sound source in a simulated engine nacelle was held at locations representative of a range of engine locations above the wing. The sound field around the model was measured, with the airframe and source in place and with source alone, using an array of microphones on a rotating hoop that is also translated along an axis parallel to the airframe axis. The insertion loss was determined from the difference between the two resulting contours. Although no attempt was made to simulate the noise characteristics of a particular engine, the broadband noise source radiated sound over a range of scaled frequencies encompassing 1 and 2 times the blade passage frequency representative of a large, high-bypass-ratio turbofan engine.
Download or read book Aircraft Configuration Noise Reduction Volume I Engineering Analysis written by D. G. Dunn and published by . This book was released on 1976 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report discusses use of wing and fuselage structures as noise barriers for shielding aircraft engine noise from the community. The report concerns use of favorable aircraft configurations for community noise reduction of turbojet and turbofan powered aircraft. Significant noise reduction potential is illustrated on a hypothetical engine-over-wing (EOW) configuration using high-bypass-ratio turbofan engines. Noise shielding estimation procedures are developed for two types of configuration noise reduction concepts; i.e., the EOW and the engine-over-fuselage (EOF). Results are described for a theoretical analysis, a major Boeing/Aeritalia test program, and an empirical analysis of test data. As a result, analytical prediction procedures are defined, computerized, and added to the software previously developed under NASA contract NAS2-6969. The shielding prediction procedures consider individual noise components: inlet fan, compressor, exit fan, core, turbine, and jet noise. A new source, jet/edge interaction noise, can also be predicted using the procedures. The collective software, incorporating the shielding package of this report, can be used to estimate community noise levels of wing and fuselage shielded turbofan or turbojet noise. This report is presented in three volumes. Volume 1 contains the engineering analysis. Volume 2 contains a User's Guide for computer programs and other appendices. Volume 3 contains the complete computer program listing. (Author).
Download or read book Small Engine Technology Set Task 13 Anopp Noise Prediction for Small Engines written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-13 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Final Report has been prepared by AlliedSignal Engines and Systems, Phoenix, Arizona, documenting work performed during the period May 1997 through June 1999, under the Small Engines Technology Program, Contract No. NAS3-27483, Task Order 13, ANOPP Noise Prediction for Small Engines. The report specifically covers the work performed under Subtasks 4, 5 and 6. Subtask 4 describes the application of a semi-empirical procedure for jet noise prediction, subtask 5 describes the development of a procedure to predict the effects of wing shielding, and subtask 6 describes the results of system studies of the benefits of the new noise technology on business and regional aircraft. Lieber, Lysbeth and Golub, Robert (Technical Monitor) Langley Research Center NAS3-27483; RTOP 538-03-13-01
Download or read book Prediction of Jet Noise Shielding with Forward Flight Effects written by Salvador Mayoral and published by . This book was released on 2013 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aircraft noise continues to be a major concern among airport-neighboring communities. A strong component of aircraft noise is the jet noise that is generated from the turbulent mixing between the jet exhaust and ambient medium. The hybrid wing body aircraft suppresses jet noise by mounting the engines over-the-wing so that the airframe may shield ground observers from jet noise sources. Subscale jet noise shielding measurements of a scaled-down turbofan nozzle and a model of the hybrid wing body planform are taken with two 12-microphone polar arrays. Chevrons and wedge-type fan flow deflectors are integrated into the baseline bypass ratio 10 (BPR10) nozzle to modify the mean flow and alter the noise source behavior. Acoustic results indicate that the baseline BPR10 nozzle produces a long noise source region that the airframe has difficulty shielding, even when the nozzle is translated two fan diameters upstream of its nominal position. The integration of either chevrons or fan flow deflectors into the nozzle is essential for jet noise shielding because they translate peak intensities upstream, closer to the fan exit plane. The numerical counterpart of this study transforms the system of equations governing the acoustic diffraction with forward flight into the wave equation. Two forward flight formulations are considered: uniform flow over slender body; and non-uniform potential flow at low Mach number. The wave equation is solved numerically in the frequency domain using the boundary element method. The equivalent jet noise source is modeled using the combination of a wavepacket and a monopole. The wavepacket is parameterized using the experimental far-field acoustic autospectra of the BPR10 jets and knowledge of their peak noise locations. It is shown that the noise source compacts with increasing Mach number and consequently there is an increase in shielding. An assessment of the error associated with the non-uniform formulation for forward flight shows that the error is low for Mach numbers less than or equal to 0.2, but can be on the same scale as the acoustic scatter field when the Mach number is 0.6.
Download or read book Aircraft Engine Noise Reduction written by and published by . This book was released on 1972 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aircraft Propulsion written by Saeed Farokhi and published by John Wiley & Sons. This book was released on 2021-09-14 with total page 1045 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explore the latest edition of a leading resource on sustainable aviation, alternative jet fuels, and new propulsion systems The newly revised Third Edition of Aircraft Propulsion delivers a comprehensive update to the successful Second Edition with a renewed focus on the integration of sustainable aviation concepts. The book tackles the impact of aviation on the environment at the engine component level, as well as the role of propulsion system integration on fuel burn. It also discusses combustion emissions, including greenhouse gases, carbon monoxide, unburned hydrocarbons (UHC), and oxides of nitrogen (NOx). Alternative jet fuels, like second generation biofuels and hydrogen, are presented. The distinguished author covers aviation noise from airframe to engine and its impact on community noise in landing and takeoff cycles. The book includes promising new technologies for propulsion and power, like the ultra-high bypass (UHB) turbofan and hybrid-electric and electric propulsion systems. Readers will also benefit from the inclusion of discussions of unsteady propulsion systems in wave-rotor combustion and pulse-detonation engines, as well as: A thorough introduction to the history of the airbreathing jet engine, including innovations in aircraft gas turbine engines, new engine concepts, and new vehicles An exploration of compressible flow with friction and heat, including a brief review of thermodynamics, isentropic process and flow, conservation principles, and Mach numbers A review of engine thrust and performance parameters, including installed thrust, rocket thrust, and modern engine architecture A discussion of gas turbine engine cycle analysis Perfect for aerospace and mechanical engineering students in the United States and overseas, Aircraft Propulsion will also earn a place in the libraries of practicing engineers in the aerospace and green engineering sectors seeking the latest up to date resource on sustainable aviation technologies.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1982 with total page 1282 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 NASA Activities written by and published by . This book was released on 1978 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Green Transportation Logistics written by Harilaos N. Psaraftis and published by Springer. This book was released on 2015-07-13 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the state of the art in green transportation logistics from the perspective of balancing environmental performance in the transportation supply chain while also satisfying traditional economic performance criteria. Part of the book is drawn from the recently completed European Union project Super Green, a three-year project intended to promote the development of European freight corridors in an environmentally friendly manner. Additional chapters cover both the methodological base and the application context of green transportation logistics. Individual chapters look at the policy context; the basics of transportation emissions; Green Corridors basics; the concept of TEN-T (Trans-European Network); Benchmarking of green corridors; the potential role of ICT (Information and Communication Technologies); Green vehicle routing; Reducing maritime CO2 emissions via market based measures and speed and route optimization; Sulphur emissions; Lifecycle emissions; Green rail transportation; Green air transportation; Green inland navigation and possible areas for further research. Throughout, the book pursues the goal of “win-win” solutions and analyzes the phenomenon of “push-down, pop-up”, wherein a change in one aspect of a problem can cause another troubling aspect to arise. For example, speed reduction in maritime transportation can reduce emissions and fuel costs, but could require additional ships and could raise in-transit inventory costs. Or, regulations to reduce sulphur emissions may ultimately increase CO2 elsewhere in the supply chain. The book takes stock at the various tradeoffs that are at stake in the goal of greening the supply chain and looks at where balances can be struck.
Download or read book Small Engine Technology SET written by Lysbeth Lieber and published by . This book was released on 2000 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AIAA 79 0631 AIAA 79 0680 With omissions in numbering written by and published by . This book was released on 1979 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Future Propulsion Systems and Energy Sources in Sustainable Aviation written by Saeed Farokhi and published by John Wiley & Sons. This book was released on 2020-01-21 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of the science and engineering behind future propulsion systems and energy sources in sustainable aviation Future Propulsion Systems and Energy Sources in Sustainable Aviation is a comprehensive reference that offers a review of the science and engineering principles that underpin the concepts of propulsion systems and energy sources in sustainable air transportation. The author, a noted expert in the field, examines the impact of air transportation on the environment and reviews alternative jet fuels, hybrid-electric and nuclear propulsion and power. He also explores modern propulsion for transonic and supersonic-hypersonic aircraft and the impact of propulsion on aircraft design. Climate change is the main driver for the new technology development in sustainable air transportation. The book contains critical review of gas turbine propulsion and aircraft aerodynamics; followed by an insightful presentation of the aviation impact on environment. Future fuels and energy sources are introduced in a separate chapter. Promising technologies in propulsion and energy sources are identified leading to pathways to sustainable aviation. To facilitate the utility of the subject, the book is accompanied by a website that contains illustrations, and equation files. This important book: Contains a comprehensive reference to the science and engineering behind propulsion and power in sustainable air transportation Examines the impact of air transportation on the environment Covers alternative jet fuels and hybrid-electric propulsion and power Discusses modern propulsion for transonic, supersonic and hypersonic aircraft Examines the impact of propulsion system integration on aircraft design Written for engineers, graduate and senior undergraduate students in mechanical and aerospace engineering, Future Propulsion Systems and Energy Sources in Sustainable Aviation explores the future of aviation with a guide to sustainable air transportation that includes alternative jet fuels, hybrid-electric propulsion, all-electric and nuclear propulsion.
Download or read book NASA Technical Paper written by and published by . This book was released on 1982 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Paper written by United States. National Aeronautics and Space Administration and published by . This book was released on 1977 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Tech Briefs written by and published by . This book was released on 2016-05 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
