Results 171 to 180 of about 30,315 (234)
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Helicopter Main-Rotor/Tail-Rotor Interaction
Journal of the American Helicopter Society, 2000Preliminary results from a study to model the interaction aerodynamics and aeroacoustics of the main and tail rotor of a helicopter in subsonic flow are presented. The configurations studied are: 1) two bladed main and tail rotors in hover, and 2) a four-bladed main rotor and two-bladed tail rotor in climbing flight.
Yin, J., Ahmed, S.R.
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Helicopter rotor thickness noise
6th Aeroacoustics Conference, 1980The attention is focused on rotor blade thickness noise (flow subsonic everywhere). The solution of the wave equation is written in a closed form (frequency domain) which emphasizes the essential parameters for this field. On another side, starting from an estimation of the loads on the rotor disk (lifting-line theory), the acoustic emission due to ...
Claude Dahan, Edmond Gratieux
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The Journal of the Acoustical Society of America, 1993
Flow separation behind the notch region of a swept tip of a helicopter rotor blade is reduced by features of the geometry and aerodynamic characteristics of the notch region itself. In particular it has been found beneficial for a forwardly swept leading edge portion to extend at an angle between 30 degrees and 55 degrees from a reference line parallel
Frederick J. Perry, Alan Brocklehurst
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Flow separation behind the notch region of a swept tip of a helicopter rotor blade is reduced by features of the geometry and aerodynamic characteristics of the notch region itself. In particular it has been found beneficial for a forwardly swept leading edge portion to extend at an angle between 30 degrees and 55 degrees from a reference line parallel
Frederick J. Perry, Alan Brocklehurst
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10th Aeroacoustics Conference, 1986
A study was made of helicopter tail rotor noise, particularly that due to interactions with the main rotor tip vortices, and with the fuselage separation mean wake. The tail rotor blade-main rotor tip vortex interaction is modelled as an airfoil of infinite span cutting through a moving vortex.
S.-T. CHOU, A. GEORGE
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A study was made of helicopter tail rotor noise, particularly that due to interactions with the main rotor tip vortices, and with the fuselage separation mean wake. The tail rotor blade-main rotor tip vortex interaction is modelled as an airfoil of infinite span cutting through a moving vortex.
S.-T. CHOU, A. GEORGE
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The Aeronautical Journal, 1970
To be asked to give the Lanchester Lecture, on the topic of helicopters, is a great honour and just now a wonderful chance. We all know of Lanchester's basic contributions to our knowledge of the way in which lift is generated by the creation of a vortex system.
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To be asked to give the Lanchester Lecture, on the topic of helicopters, is a great honour and just now a wonderful chance. We all know of Lanchester's basic contributions to our knowledge of the way in which lift is generated by the creation of a vortex system.
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The Journal of the Helicopter Association of Great Britain, 1948
Ladies and Gentlemen,It is with pleasure that I introduce to you today MR MCCLEMENTS, who is going to talk to us on the subject of “Helicopter Rotors”MR McCLEMENTS is a relatively newcomer to the rotary wing industry and only claims a modest two years or so of direct connection, first with the Ministry of Supply and now as experimental engineer to the ...
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Ladies and Gentlemen,It is with pleasure that I introduce to you today MR MCCLEMENTS, who is going to talk to us on the subject of “Helicopter Rotors”MR McCLEMENTS is a relatively newcomer to the rotary wing industry and only claims a modest two years or so of direct connection, first with the Ministry of Supply and now as experimental engineer to the ...
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2017
The theory discussed in previous chapters is now applied to a helicopter rotor. The results are matched with published literature. A MATLAB code is given along with this book which can be used to generate results given in this chapter.
Ranjan Ganguli, Vijay Panchore
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The theory discussed in previous chapters is now applied to a helicopter rotor. The results are matched with published literature. A MATLAB code is given along with this book which can be used to generate results given in this chapter.
Ranjan Ganguli, Vijay Panchore
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2001
This effort was directed toward demonstration of the efficacy of a concept for mitigation of the rotor blade modulation problem in helicopter communications. An antenna is envisioned with radiating elements mounted on the rotor and rotating with it. The rf signals are coupled to the radio stationary with respect to the airframe via a coupler of unique ...
Vaughn P. Cable, Ronald J. Pogorzelski
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This effort was directed toward demonstration of the efficacy of a concept for mitigation of the rotor blade modulation problem in helicopter communications. An antenna is envisioned with radiating elements mounted on the rotor and rotating with it. The rf signals are coupled to the radio stationary with respect to the airframe via a coupler of unique ...
Vaughn P. Cable, Ronald J. Pogorzelski
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Aerodynamics and aeroacoustics of helicopter main-rotor/tail-rotor interaction
5th AIAA/CEAS Aeroacoustics Conference and Exhibit, 1999Preliminary results from an ongoing effort to model the interaction aerodynamics and aeroacoustics of main- and tail rotor of a helicopter in subsonic flow are presented. The configurations studied are a) a two-blade main- and tail rotor in hover, and b) a four-blade main- and a two-blade tail rotor in climb flight.
Ahmed, S.R., Yin, J.
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