Results 261 to 270 of about 15,235 (310)

On the stability of rotating blade arrays

Journal of Sound and Vibration, 2004
Abstract A mathematical model consisting of an array of rotating pendulums was built to study the stability of an array of rotating blades and the dynamic interaction between the blades and the rotor. This model can be solved in closed form, yielding some general results regarding the stability of the system, particularly for the effects of the blade–
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Untwist of Rotating Blades

Journal of Engineering for Power, 1975
This paper deals with the deformation and the stress of an axial flow compressor rotor blade under the loading of centrifugal forces. Coupled deformation of extension, bending, torsion and transverse shear of a pretwisted curved bar with arbitrary cross section is considered.
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Vibrations of Twisted Rotating Blades

Journal of Vibration and Acoustics, 1984
The literature dealing with vibrations of turbomachinery blades is voluminous, but the vast majority of it treats the blades as beams. In a previous paper a two-dimensional analytical procedure was developed and demonstrated on simple models of blades having camber.
A. W. Leissa, J. K. Lee, A. J. Wang
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An OPR-Free Blade Tip Timing Method for Rotating Blade Condition Monitoring

IEEE Transactions on Instrumentation and Measurement, 2021
Blade tip timing (BTT) is a noncontact blade vibration measurement method for rotating blade condition monitoring. However, it is difficult to install a once-per-revolution (OPR) probe due to the internal environment limitation of an engine. To solve this problem, an OPR-free BTT method is proposed in this article.
Zengkun Wang, Zhibo Yang 0001, Shuming Wu, Haoqi Li, Shaohua Tian, Xingwu Zhang, Ruqiang Yan 0001, Xuefeng Chen 0002   +7 more
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The Laminar Boundary Layer on a Rotating Blade

Journal of the Aeronautical Sciences, 1951
Boundary-layer equations of motion for a blade rotating steadily in an incompressible fluid are developed. The equations show that , at stations several chord lengths from the axis of rotation of a thin blade, the chordwise velocity is independent of the spanwise velocity due to rotation; hence, the separation line is unaffected by rotation.
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One-blade rotation of a persistent posterior vertex

American Journal of Obstetrics and Gynecology, 1991
Fifteen women in labor at term with no evidence of protraction or arrest disorder successfully underwent a single-blade rotation of the fetus from occipitoposterior to occipitoanterior position. There were no failures, no fetal injuries, and no significant maternal trauma.
J O, Escamilla, S J, Carlan
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Rotating blades and aerodynamic sound

Journal of Sound and Vibration, 1973
The history of research on rotating blade noise is reviewed, from early studies of propeller radiation to current work on aircraft-engine fans. The survey is selective, with emphasis on fundamental aspects of aerodynamic sound generation by blades. The topics covered include the following: early research on propeller noise, unsteady airfoil theory ...
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Analysis of Incompressible, Nonviscous Blade-to-Blade Flow in Rotating Blade Rows

Journal of Fluids Engineering, 1958
Abstract A method is developed for the blade-to-blade solution of the incompressible, nonviscous flow through rotating blade rows (including the inlet region) with or without splitter vanes. Splitter vanes are partial blades which do not extend to the inlet of the blade row.
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The Acoustic Analogy and the Prediction of the Noise of Rotating Blades

Theoretical and Computational Fluid Dynamics, 1998
The paper focuses on the prediction of the noise of rotating machinery. The governing Ffowcs Williams-Hawkings (FW-H) equation for this problem is a wave equation for perturbation density with three source terms, which are known as thickness, loading, and the quadrupole source terms.
Farassat, F., Brentner, Kenneth S.
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Stress Analysis of the Rotating Circular Saw Blade

Solid State Phenomena, 2017
The article deals with the determination of parameters of longitudinal wood cutting by circular saw blade and construction of the cutting tool. A computational model was chosen to determine stress of the rotating circular saw blade. Stress analysis revealed that maximal stress caused by the temperature gradient was approximately ten times higher than ...
Bílek, Ondřej, Kovařík, Martin
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