Next Article in Journal
Performance Analysis of a RED-MED Salinity Gradient Heat Engine
Previous Article in Journal
Winding Design and Analysis for a Disc-Type Permanent-Magnet Synchronous Motor with a PCB Stator
Article Menu

Export Article

Open AccessArticle
Energies 2018, 11(12), 3384; https://doi.org/10.3390/en11123384

On the Dynamics of Flexible Plates under Rotational Motions

1
College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210024, China
2
Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA
3
State Key Laboratory of Hydroscience and Engineering & Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
4
Department of Aerospace Engineering, University of Illinois, Urbana, IL 61801, USA
5
Department of Civil and Environmental Engineering, University of Illinois, Urbana, IL 61801, USA
*
Author to whom correspondence should be addressed.
Received: 5 November 2018 / Revised: 22 November 2018 / Accepted: 28 November 2018 / Published: 3 December 2018
Full-Text   |   PDF [4225 KB, uploaded 3 December 2018]   |  

Abstract

The reconfiguration of low-aspect-ratio flexible plates, required power and induced flow under pure rotation were experimentally inspected for various plate stiffness and angular velocities ω. Particle tracking velocimetry (PTV) and particle image velocimetry (PIV) were used to characterize the plate deformation along their span as well as the flow and turbulence statistics in the vicinity of the structures. Results show the characteristic role of stiffness and ω in modulating the structure reconfiguration, power required and induced flow. The inspected configurations allowed inspecting various plate deformations ranging from minor to extreme bending over 90 between the tangents of the two tips. Regardless of the case, the plates did not undergo noticeable deformation in the last ∼30% of the span. Location of the maximum deformation along the plate followed a trend s m l o g ( C a ) , where C a is the Cauchy number, which indicated that s m is roughly fixed at sufficiently large C a. The angle (α) between the plate in the vicinity of the tip and the tangential vector of the motions exhibited two distinctive, nearly-linear trends as a function of C a , within C a ( 0 , 15 ) and C a ( 20 , 70 ), with a matching within these C a at C a > 70, α 45 . Induced flow revealed a local maximum of the turbulence levels at around 60% of the span of the plate; however, the largest turbulence enhancement occurred near the tip. Flexibility of the plate strongly modulated the spatial distribution of small-scale vortical structures; they were located along the plate wake in the stiffer plate and relatively concentrated near the tip in the low-stiffness plate. Due to relatively large deformation, rotational and wake effects, a simple formulation for predicting the mean reconfiguration showed offset; however, a bulk, constant factor on ω accounted for the offset between predictions and measurements at deformation reaching ∼ 60 between the tips. View Full-Text
Keywords: PIV; plate oscillation; rotation; turbulence PIV; plate oscillation; rotation; turbulence
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Fu, S.; Jin, Y.; Kim, J.-T.; Mao, Z.; Zheng, Y.; Chamorro, L.P. On the Dynamics of Flexible Plates under Rotational Motions. Energies 2018, 11, 3384.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Energies EISSN 1996-1073 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top