Results 11 to 20 of about 293,907 (269)
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
Helicopter tail rotor thrust and main rotor wake coupling in crosswind flight [PDF]
, 2010 The tail rotor of a helicopter with a single main rotor configuration can experience a significant reduction in thrust when the aircraft operates in crosswind flight. Brown’s vorticity transport model has been used to simulate a main rotor and tail rotor
Fletcher, Timothy M., Brown, Richard
core +4 more sources
Main rotor-tail rotor intraction and its implications for helicopter directional control [PDF]
, 2008 Aerodynamic interference between the main and tail rotor can have a strong negative influence on the flight mechanics of a conventional helicopter. Significant unsteadiness in the tail rotor loading is encountered under certain flight conditions, but the
Fletcher, Timothy M., Brown, R.E.
core +4 more sources
Ground effect on a rotor wake. [PDF]
, 1985 The effect of the ground on a rotor wake in forward flight has been investigated experimentally in the working section of an 8ft x Oft straight-through wind tunnel.
Kusmarwanto, I.
core +7 more sources
A High-Resolution Self-Powered Angular Displacement Sensor Based on Triboelectric Nanogenerator With Time-Grating. [PDF]
Adv Sci (Weinh)A self‐powered phase‐encoding sensing paradigm enables direct motion‐to‐time information conversion, providing a compact and autonomous strategy for high resolution angular displacement measurement. ABSTRACT In modern manufacturing and engineering, angular displacement sensors are crucial for motion control and feedback systems in Electromechanical ...
Wang S, An D, Liu S, Wu Z.
europepmc +2 more sources
Machines, 2022 The spindle and grinding wheel flange (GWF) adopt double positioning of a tapered surface and end face. Due to the processing quality, the contact state of the spindle–GWF interface cannot be determined accurately.
Qianqian Yuan +3 more
doaj +1 more source
Physical Review Letters, 2021 A probability density function describing the angular evolution of a fixed-length atom-atom vector as a Lévy rotor is derived containing just two dynamical parameters: the Lévy parameter $α$ and a rotational time constant $τ$. A Lévy parameter $α\!
Faux, David A. +2 more
openaire +4 more sources
Lubricants, 2023 To study the variation rules of nonlinear stiffness of double-row angular contact ball bearings (DR-ACBB), this paper proposed a general mathematic model for DR-ACBB under three different configurations based on the improved quasi-static model of ball ...
Bin Fang, Jinhua Zhang, Jun Hong, Ke Yan
doaj +1 more source
A comparison of coaxial and conventional rotor performance [PDF]
, 2010 The performance of a coaxial rotor in hover, in steady forward flight, and in level, coordinated turns is contrasted with that of an equivalent, conventional rotor with the same overall solidity, number of blades, and blade aerodynamic properties.
Brown, Richard E., Kim, Hyo Won
core +4 more sources