Results 11 to 20 of about 1,176,775 (247)
Aeroacoustic analysis of main rotor and tail rotor interaction [PDF]
, 2008 The increased restrictions placed on helicopter noise levels over recent decades have encouraged manufacturers to better understand tail rotor noise and its aerodynamic sources.
Fletcher, Timothy M. +5 more
core +13 more sources
Aeroacoustics of a coaxial rotor in level flight [PDF]
, 2008 The aeroacoustic characteristics of a coaxial system with teetering rotors in level forward °ight are com- pared to those of an equivalent articulated single rotor with the same solidity.
Brown, R.E. +5 more
core +12 more sources
Sensitivity of tail rotor noise to helicopter configuration in forward flight [PDF]
, 2009 Understanding the mechanisms that lead to the production of noise by tail rotors across a broad range of flight conditions and helicopter configurations remains an active area of research.
Fletcher, Timothy M. +2 more
core +9 more sources
IEEE Open Journal of Industry Applications, 2020 Compared with internal-rotor switched reluctance motors (SRMs), external-rotor (ER) SRMs can show different vibration and acoustic noise behavior due to the differences in the designs, e.g.
Jianbin Liang +3 more
doaj +1 more source
Shielding of rotor noise by plates and wings
Acta Acustica, 2022 A method of noise reduction proposed for the next generation of aircraft is to shield noise from the propulsion system, by positioning the noise source over a wing or another surface.
Carley Michael
doaj +1 more source
Machines, 2022 In this paper, we designed flat conductor winding permanent magnet synchronous motors with three different rotor structures under certain boundary conditions.
Kai Zhao, Jian Luo
doaj +1 more source
Aerospace, 2022 The accurate prediction of helicopter rotor blade–vortex interaction (BVI) noise is challenging. This paper presents an implementation of the seventh-order improved weighted essentially non-oscillatory (WENO-Z) scheme for predicting rotor BVI noise using
Yan Sun, Yongjie Shi, Guohua Xu
doaj +1 more source
Nonharmonic Control of the Blade-Vortex Interaction Noise of Electrically Controlled Rotor
International Journal of Aerospace Engineering, 2022 Electrically controlled rotor, also known as swashplateless rotor, represents an active rotor system that, due to the use of a trailing edge flap system instead of a swashplate, not only enables primary control but also conveniently reduces the blade ...
Kewei Li +3 more
doaj +1 more source
Hydrodynamic Effect of Highly Skewed Horizontal-Axis Tidal Turbine (HATT) Rotors
Energies, 2023 While hydro turbines generate over 40% of the world’s total renewable energy, these traditional turbines present a great environmental concern due to the potential of their sharp blades to damage aquatic lives and ecology, along with their harmful noise ...
Yiyi Xu, Juin Ming Foong, Pengfei Liu
doaj +1 more source
Machines, 2023 Research on helicopter transient maneuvering flight noise is a hotspot and challenging topic in the fields of helicopter design and application. A new time-accurate free-wake (TAFW) method and the Fowcs Williams-Hawkings (FW–H) equations are applied to ...
Zhiyuan Hu +3 more
doaj +1 more source