New Computational Methods for the Prediction and Analysis of Helicopter Noise

New Computational Methods for the Prediction and Analysis of Helicopter Noise PDF Author: Roger C. Strawn
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 18

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Book Description
Abstract: "This paper describes several new methods to predict and analyze rotorcraft noise. These methods are: 1) a combined computational fluid dynamics and Kirchhoff scheme for far-field noise predictions, 2) parallel computer implementation of the Kirchhoff integrations, 3) audio and visual rendering of the computed acoustic predictions over large far-field regions, and 4) acoustic tracebacks to the Kirchhoff surface to pinpoint the sources of the rotor noise. The paper describes each method and presents sample results for three test cases. The first case consists of in-plane high-speed impulsive noise and the other two cases show idealized parallel and oblique blade-vortex interactions. The computed results show good agreement with available experimental data but convey much more information about the far-field noise propagation. When taken together, these new analysis methods exploit the power of new computer technologies and offer the potential to significantly improve our prediction and understanding of rotorcraft noise."

New Computational Methods for the Prediction and Analysis of Helicopter Noise

New Computational Methods for the Prediction and Analysis of Helicopter Noise PDF Author: Roger C. Strawn
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 18

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Book Description
Abstract: "This paper describes several new methods to predict and analyze rotorcraft noise. These methods are: 1) a combined computational fluid dynamics and Kirchhoff scheme for far-field noise predictions, 2) parallel computer implementation of the Kirchhoff integrations, 3) audio and visual rendering of the computed acoustic predictions over large far-field regions, and 4) acoustic tracebacks to the Kirchhoff surface to pinpoint the sources of the rotor noise. The paper describes each method and presents sample results for three test cases. The first case consists of in-plane high-speed impulsive noise and the other two cases show idealized parallel and oblique blade-vortex interactions. The computed results show good agreement with available experimental data but convey much more information about the far-field noise propagation. When taken together, these new analysis methods exploit the power of new computer technologies and offer the potential to significantly improve our prediction and understanding of rotorcraft noise."

Army RD & A.

Army RD & A. PDF Author:
Publisher:
ISBN:
Category : Military research
Languages : en
Pages : 380

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Book Description
Professional publication of the RD & A community.

Journal of Aircraft

Journal of Aircraft PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 388

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Army RD & A Bulletin

Army RD & A Bulletin PDF Author:
Publisher:
ISBN:
Category : Military research
Languages : en
Pages : 64

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2nd AIAA/CEAS Aeroacoustics Conference

2nd AIAA/CEAS Aeroacoustics Conference PDF Author:
Publisher:
ISBN:
Category : Aerodynamic noise
Languages : en
Pages : 622

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Journal of the American Helicopter Society

Journal of the American Helicopter Society PDF Author: American Helicopter Society
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 344

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Principles of Helicopter Aerodynamics with CD Extra

Principles of Helicopter Aerodynamics with CD Extra PDF Author: Gordon J. Leishman
Publisher: Cambridge University Press
ISBN: 9780521858601
Category : Science
Languages : en
Pages : 860

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Book Description
Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.

Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 702

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Calculation of Complex Turbulent Flows

Calculation of Complex Turbulent Flows PDF Author: George Tzabiras
Publisher: Witpress
ISBN:
Category : Science
Languages : en
Pages : 424

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Book Description
A selection of invited chapters focusing on developments in the application of Computational Fluid Dynamics (CFD) to compressible or incompressible flows dominated by turbulence effects. These may be applied to complex geometrical configurations or flow-fields in simpler geometries requiring higher-order turbulence modelling, or suitably modified low-order models, to calculate crucial parameters such as instabilities, transition, separation, accurate description of velocity and scalar fields, and local and total forces.

International Aerospace Abstracts

International Aerospace Abstracts PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 940

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Book Description