Open Rotor Noise Prediction at NASA Langley - Capabilities, Research and Development

Open Rotor Noise Prediction at NASA Langley - Capabilities, Research and Development

Author: National Aeronautics and Space Adm Nasa

Publisher: Independently Published

Published: 2019-01-13

Total Pages: 32

ISBN-13: 9781793923035

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The high fuel prices of recent years have caused the operating cost of the airlines to soar. In an effort to bring down the fuel consumption, the major aircraft engine manufacturers are now taking a fresh look at open rotors for the propulsion of future airliners. Open rotors, also known as propfans or unducted fans, can offer up to 30 per cent improvement in efficiency compared to high bypass engines of 1980 vintage currently in use in most civilian aircraft. NASA Langley researchers have contributed significantly to the development of aeroacoustic technology of open rotors. This report discusses the current noise prediction technology at Langley and reviews the input data requirements, strengths and limitations of each method as well as the associated problems in need of attention by the researchers. We present a brief history of research on the aeroacoustics of rotating blade machinery at Langley Research Center. We then discuss the available noise prediction codes for open rotors developed at NASA Langley and their capabilities. In particular, we present the two useful formulations used for the computation of noise from subsonic and supersonic surfaces. Here we discuss the open rotor noise prediction codes ASSPIN and one based on Ffowcs Williams-Hawkings equation with penetrable data surface (FW - Hpds). The scattering of sound from surfaces near the rotor are calculated using the fast scattering code (FSC) which is also discussed in this report. Plans for further improvements of these codes are given. Farassat, Fereidoun Langley Research Center WBS:561581.02.08.07.18.03


Advanced Aircraft Design

Advanced Aircraft Design

Author: Egbert Torenbeek

Publisher: John Wiley & Sons

Published: 2013-05-28

Total Pages: 412

ISBN-13: 1118568095

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Although the overall appearance of modern airliners has not changed a lot since the introduction of jetliners in the 1950s, their safety, efficiency and environmental friendliness have improved considerably. Main contributors to this have been gas turbine engine technology, advanced materials, computational aerodynamics, advanced structural analysis and on-board systems. Since aircraft design became a highly multidisciplinary activity, the development of multidisciplinary optimization (MDO) has become a popular new discipline. Despite this, the application of MDO during the conceptual design phase is not yet widespread. Advanced Aircraft Design: Conceptual Design, Analysis and Optimization of Subsonic Civil Airplanes presents a quasi-analytical optimization approach based on a concise set of sizing equations. Objectives are aerodynamic efficiency, mission fuel, empty weight and maximum takeoff weight. Independent design variables studied include design cruise altitude, wing area and span and thrust or power loading. Principal features of integrated concepts such as the blended wing and body and highly non-planar wings are also covered. The quasi-analytical approach enables designers to compare the results of high-fidelity MDO optimization with lower-fidelity methods which need far less computational effort. Another advantage to this approach is that it can provide answers to “what if” questions rapidly and with little computational cost. Key features: Presents a new fundamental vision on conceptual airplane design optimization Provides an overview of advanced technologies for propulsion and reducing aerodynamic drag Offers insight into the derivation of design sensitivity information Emphasizes design based on first principles Considers pros and cons of innovative configurations Reconsiders optimum cruise performance at transonic Mach numbers Advanced Aircraft Design: Conceptual Design, Analysis and Optimization of Subsonic Civil Airplanes advances understanding of the initial optimization of civil airplanes and is a must-have reference for aerospace engineering students, applied researchers, aircraft design engineers and analysts.


The Smell of Kerosene

The Smell of Kerosene

Author: National Aeronautics and Space Administration

Publisher: DigiCat

Published: 2022-11-13

Total Pages: 276

ISBN-13:

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This book puts the reader in the pilot's seat for a "day at the office" unlike any other. The Smell of Kerosene tells the dramatic story of a NASA research pilot who logged over 11,000 flight hours in more than 125 types of aircraft. Donald Mallick gives the reader fascinating first-hand description of his early naval flight training, carrier operations, and his research flying career with NASA. After transferring to the NASA Flight Research Center, Mallick became involved with projects that further pushed the boundaries of aerospace technology. These included the giant delta-winged XB-70 supersonic airplane, the wingless M2-F1 lifting body vehicle, and triple-sonic YF-12 Blackbird. Mallick also test flew the Lunar Landing Research Vehicle and helped develop techniques used in training astronauts to land on the Moon.