Cross-Sectional Parameters of Cotton Fibers

Presented paper deals with modelling of a twisted blade with rhombic shroud as one-dimensional continuum by means of Rayleigh beam finite elements with varying cross-sectional parameters along the finite elements. The blade is clamped into a rotating rigid disk and the shroud is considered to be a rigid body. Since the finite element models based on the Rayleigh beam theory tend to slightly overestimate natural frequencies and underestimate deflections in comparison with finite element models including shear deformation effects, parameter tuning of the blade is performed.

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Characterization of drag reduction performance over rotating microgrooves with different cross-sections

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407019882557 ◽

2019 ◽

Vol 234 (6) ◽

pp. 1746-1758

Author(s):

Suping Wen ◽

Wenbo Wang ◽

Zhixuan Zhang

Keyword(s):

Drag Reduction ◽

Cross Sections ◽

Turbulence Intensity ◽

Reynolds Numbers ◽

Cross Sectional ◽

Dimensionless Velocity ◽

Velocity Shift ◽

Maximum Drag Reduction ◽

Sectional Parameters

This paper presents a study of cross-sectional parameters and optimal drag reduction performance specifically for drag reduction in rotating microgroove applications. Rotating triangular microgrooves with nine asymmetrical and symmetrical cross-sections were numerically studied. In addition, a representative symmetrical rotating microgroove was experimentally tested. Positive asymmetrical microgrooves (including symmetrical microgrooves) were found to be sensitive to rotating Reynolds numbers and produced more significant drag reduction. Compared with a dimensioned asymmetry variable and other dimensionless parameters, the dimensionless asymmetry variable i+ could be used to describe drag reduction performance, which captured both the influence of microgroove cross-sectional asymmetry and turbulence intensity. A maximum drag reduction of up to 8.9% was obtained at 9.2 i+. With the exception of the torque, the velocity shift obtained from dimensionless velocity profiles could also be used to predict drag reduction performance, which has the potential for wider and more comprehensive application for any drag reduction technology.

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Determination of collision cross-sectional parameters from experimentally measured gas diffusion coefficients

Fluid Phase Equilibria ◽

10.1016/j.fluid.2003.12.010 ◽

2004 ◽

Vol 218 (2) ◽

pp. 177-188 ◽

Cited By ~ 27

Author(s):

Dimitrios Gavril ◽

Khan Rashid Atta ◽

George Karaiskakis

Keyword(s):

Diffusion Coefficients ◽

Gas Diffusion ◽

Cross Sectional ◽

Sectional Parameters

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Effect of uncertainties in the cross-sectional parameters on the wideband electrical properties of coplanar waveguides

2007 IEEE Workshop on Signal Propagation on Interconnects ◽

10.1109/spi.2007.4512202 ◽

2007 ◽

Cited By ~ 2

Author(s):

J. Leinhos ◽

U. Arz

Keyword(s):

Electrical Properties ◽

Coplanar Waveguides ◽

Cross Sectional ◽

The Cross ◽

Sectional Parameters

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Simultaneous Optimization of Structure and Control for Vibration Suppression

Journal of Vibration and Acoustics ◽

10.1115/1.2893970 ◽

1999 ◽

Vol 121 (2) ◽

pp. 237-243 ◽

Cited By ~ 10

Author(s):

Ye Zhu ◽

Jinhao Qiu ◽

Junji Tani ◽

Yuta Urushiyama ◽

Yasuharu Hontani

Keyword(s):

Structural Optimization ◽

Vibration Suppression ◽

Optimization Problems ◽

Simultaneous Optimization ◽

Control Input ◽

Cross Sectional ◽

Traditional Design ◽

Simulation Results ◽

Sectional Parameters ◽

And Control

A method of simultaneous optimization of structure and control using mixed H2 and H∞ norms of the transfer function as the objective function is proposed and the modeling and formulation of simultaneous optimization problems associated with this approach are discussed in this paper. Simultaneous optimization is realized by iteratively executing structural optimization and controller optimization. Both serial and parallel approaches to combine structural optimization and controller optimization are investigated. They are applied to the simultaneous optimization of the cross-sectional parameters of a spring-supported beam and the parameters of the controller used to actively suppress the vibration of the beam. The performance of both displacement output and control input is improved significantly after simultaneous optimization. The simulation results show the great potential advantages of simultaneous optimization over traditional design methods and the effectiveness of the proposed approach.

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