Results 271 to 280 of about 15,235 (310)

An Exploration of Radial Flow on a Rotating Blade in Retreating Blade Stall

Journal of the American Helicopter Society, 2013
The nature of radial flow during retreating blade stall on a two-bladed teetering rotor with cyclic pitch variation is investigated using laser sheet visualization and particle image velocimetry in a low-speed wind tunnel. The velocity field above the retreating blade at 270◦ azimuth shows the expected development of a radially directed jet layer close
Vrishank Raghav, Narayanan Komerath
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Physics-Guided Sound Synthesis for Rotating Blades

2020
This paper focuses on sound synthesis for rotating blades such as fans, helicopters and wind turbines, which is common in both real world and computer games though has received little attention until now. In this paper, we propose a novel physics-guided sound synthesis method for rotating blades.
Siqi Xu, Shiguang Liu
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The Effect of Blade Geometry on the Normal Force Distribution of a Rotating Blade

43rd AIAA Aerospace Sciences Meeting and Exhibit, 2005
The effect of rotation on the segment cn characteristics has been investigated with emphasis on the consequences of the blade geometry. The data used came from field tests and wind tunnel experiments performed by NREL (National Renewable Energy Laboratory) on rotor blades with pressure measurements at different radial positions.
Ruud Rooij, Gerard Schepers
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THE EFFECT OF BLADE CRACK ON MODE LOCALIZATION IN ROTATING BLADED DISKS

Journal of Sound and Vibration, 1999
Abstract The effects of blade crack on mode localization in rotating bladed disks are investigated in this study. A disk consisting of periodic shrouded blades is used to simulate the bladed disk of a turbo-rotor. Blades on the disk are approximated as Euler–Bernoulli beams. A crack in the blade is regarded as a local disorder of the system.
J.H. KUANG, B.W. HUANG
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Dynamics of Cracked Rotating Blades

Applied Mechanics Reviews, 1991
The modeling and formulation of equations of motion for a cracked rotating blade are studied. The proposed model is a Bernoulli-Euler beam with a single transverse crack. Two fields are connected by a local spring element characterizing the reduced stiffness of the crack region. First, the governing nonlinear boundary value problem is derived.
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Vibrations of Cracked Rotating Blades

1992
A rotating blade with a single transverse crack is considered. The proposed model is a torsionally rigid, non-pretwisted Bernoulli-Euler beam of extremely different bending stiffnesses. Two fields are connected by a local spring element characterizing the reduced stiffness of the crack region. The governing nonlinear boundary value problem is solved in
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Bending Vibration of a Rotating Blade Vibrating in the Plane of Rotation

Journal of Applied Mechanics, 1949
Abstract An analysis is developed for the uncoupled bending vibration of a rotating blade which is vibrating in the plane of rotation. The numerical method used permits the determination of any mode of vibration by a series of tabular calculations.
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Modal identification of a rotating blade system

24th Structures, Structural Dynamics and Materials Conference, 1983
A new testing technique and the Ibrahim time-domain (ITD) modal identification algorithm have been combined, resulting in a capability to estimate modal parameters for rotating-blade systems. This capability has been evaluated on the Sandia two-meter, vertical-axis wind turbine.
T. CARNE, D. MARTINEZ, S. IBRAHIM
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Delayed Stall Modeling of the Rotating Blades

AIP Conference Proceedings, 2010
Most aerodynamic design tools for horizontal‐axial wind turbines are based on the blade‐element momentum theory (BEM). Due to the nature of this theory, the design tools need 2‐D steady sectional lift and drag curves as an input. In practice, flow over a wind turbine rotor blade is neither two‐dimensional nor steady, and is affected by rotation ...
Alexandru Dumitrache, Vladimir Cardos, Horia Dumitrescu, Theodore E. Simos, George Psihoyios, Ch. Tsitouras   +5 more
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Rotating vibration behavior of the turbine blades with different groups of blades

Journal of Sound and Vibration, 2004
Abstract The rotating vibration behaviors of full cycle of 60 blades are studied in this report. The dynamic analysis of two different structures in one of which there are 10 groups of 6 blades and in the other 5 groups of 12 blades, is performed to investigate behavior deviation.
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