Download or read book Advancing Side Directivity and Retreating Side Interactions of Model Rotor Blade Vortex Interaction Noise written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic data are presented from a 40 percent scale model of the four-bladed BO-105 helicopter main rotor, tested in a large aerodynamic wind tunnel. Rotor blade-vortex interaction (BVI) noise data in the low-speed flight range were acquired using a traversing in-flow microphone array. Acoustic results presented are used to assess the acoustic far field of BVI noise, to map the directivity and temporal characteristics of BVI impulsive noise, and to show the existence of retreating-side BVI signals. The characterics of the acoustic radiation patterns, which can often be strongly focused, are found to be very dependent on rotor operating condition. The acoustic signals exhibit multiple blade-vortex interactions per blade with broad impulsive content at lower speeds, while at higher speeds, they exhibit fewer interactions per blade, with much sharper, higher amplitude acoustic signals. Moderate-amplitude BVI acoustic signals measured under the aft retreating quadrant of the rotor are shown to originate from the retreating side of the rotor. Martin, R. M. and Splettstoesser, W. R. and Elliott, J. W. and Schultz, K.-J. Langley Research Center RTOP 505-61-51-06...

Download or read book Advancing side Directivity and Retreating side Interactions of Model Rotor Blade vortex Interaction Noise written by Ruth McVoy Martin and published by . This book was released on 1988 with total page 48 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 1988 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Acoustic Measurements from a Rotor Blade vortex Interaction Noise Experiment in the German Dutch Wind Tunnel DNW written by Ruth McVoy Martin and published by . This book was released on 1988 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic data are presented from a 40-percent-scale model of the four-bladed BO-105 helicopter main rotor, tested in a large aeroacoustic wind tunnel. Rotor blade-vortex interaction (BVI) noise data in the low-speed flight range were acquired using a traversing in-flow microphone array. The experimental apparatus, testing procedures, calibration results, and experimental objectives are fully described. A large representative set of averaged acoustic signals are presented.

Download or read book NASA Technical Paper written by and published by . This book was released on 1990 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Acoustic Measurements from a Rotor Blade vortex Interaction Noise Experiment in the German Dutch Wind Tunnel DNW written by and published by . This book was released on 1988 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wake Geometry Effects on Rotor Blade vortex Interaction Noise Directivity written by Ruth McVoy Martin and published by . This book was released on 1990 with total page 32 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 1991 with total page 252 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 NASA Scientific and Technical Publications written by and published by . This book was released on 1989 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Noise and Vibration Control written by Malcolm J. Crocker and published by John Wiley & Sons. This book was released on 2007-10-05 with total page 1594 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two of the most acclaimed reference works in the area of acoustics in recent years have been our Encyclopedia of Acoustics, 4 Volume set and the Handbook of Acoustics spin-off. These works, edited by Malcolm Crocker, positioned Wiley as a major player in the acoustics reference market. With our recently published revision of Beranek & Ver's Noise and Vibration Control Engineering, Wiley is a highly respected name in the acoustics business. Crocker's new handbook covers an area of great importance to engineers and designers. Noise and vibration control is one largest areas of application of the acoustics topics covered in the successful encyclopedia and handbook. It is also an area that has been under-published in recent years. Crocker has positioned this reference to cover the gamut of topics while focusing more on the applications to industrial needs. In this way the book will become the best single source of need-to-know information for the professional markets.

Download or read book NASA Reference Publication written by and published by . This book was released on 1977 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeroacoustics of Flight Vehicles written by Harvey H. Hubbard and published by . This book was released on 1991 with total page 616 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 1988 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Blade vortex Interaction Noise Generation and Directionality written by Wel-Chong Sim and published by . This book was released on 1996 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of the American Helicopter Society written by American Helicopter Society and published by . This book was released on 1998 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt: