Results 91 to 100 of about 66,325 (272)
Investigation of the Effect of Blade Sweep on Rotor Vibratory Loads [PDF]
The effect of helicopter rotor blade planform sweep on rotor vibratory hub, blade, and control system loads has been analytically investigated. The importance of sweep angle, sweep initiation radius, flap bending stiffness and torsion bending stiffness ...
Tarzanin, F. J., Jr., Vlaminck, R. R.
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Performance Data from a Wind-Tunnel Test of Two Main-rotor Blade Designs for a Utility-Class Helicopter [PDF]
An investigation was conducted in the NASA Langley Transonic Dynamics Tunnel to evaluate an advanced main rotor designed for use on a utility class helicopter, specifically the U.S. Army UH-60A Blackhawk.
Singleton, Jeffrey D. +2 more
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Simulation of tail boom vibrations using main rotor-fuselage Computational Fluid Dynamics (CFD) [PDF]
, 2017 In this work, fully-resolved rotor-fuselage interactional aerodynamics is used as the forcing term in a model based on the Euler-Bernoulli equation, aiming to simulate helicopter tail-boom vibration.
Barakos, George N. +4 more
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Performance of an optimized rotor blade at off-design flight conditions [PDF]
An investigation is made of the dynamic and aerodynamic performance of a helicopter rotor previously optimized for minimum 4/rev vertical shear and blade weight subject to certain dynamic and structural constraints.
Chattopadhyay, Aditi
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Numerical modelling of the aerodynamic interference between helicopter and ground obstacles [PDF]
, 2017 Helicopters are frequently operating in confined areas where the complex flow fields that develop in windy conditions may result in dangerous situations.
Barakos, George N. +3 more
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Jixie chuandong, 2017 The torsional vibration dynamics analytical model of rotor power transmission system is built,the shimmy collectivity mode of vibration and frequency of rotor blade are obtained,it is indicated that the propulsion/transmission system will influence ...
Lai Lingyun, Zhang Ruochen, Liu Yongzhi
doaj
Structural optimization of composite helicopter rotor blades
, 2020 Structural optimization of a helicopter rotor blade with uniform aerodynamic surface and twist at the functional region is performed for weight minimization subject to various constraints relevant to helicopter rotor blades. The genetic algorithm based optimization is performed only for the functional region of the blade.
openaire +2 more sources
Calculated Hovering Helicopter Flight Dynamics with a Circulation Controlled Rotor [PDF]
The influence of the rotor blowing coefficient on the calculated roots of the longitudinal and lateral motion was examined for a range of values of the rotor lift and the blade flap frequency.
Chopra, I., Johnson, W.
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Tiltrotor CFD part I: validation [PDF]
, 2017 This paper presents performance analyses of the model-scale ERICA and TILTAERO tiltrotors and of the full-scale XV-15 rotor with high-fidelity computational fluids dynamics.
Barakos, George N. +2 more
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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.
Brown, R.E. +2 more
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