Fluctuating lift on a circular cylinder: review and new measurements
TL;DR: In this article, the effects of Reynolds number in the nominal case of an infinitely long and non-confined cylinder in a smooth oncoming flow are discussed, from about Re = 47 to 2 x 10(5), i.e., from the onset of vortex shedding up to the end of the subcritical regime.
About: This article is published in Journal of Fluids and Structures.The article was published on 2003-01-01. It has received 939 citations till now. The article focuses on the topics: Lift coefficient & Reynolds number.
Citations
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TL;DR: A comprehensive review of the progress made during the past two decades on vortex-induced vibration (VIV) of mostly circular cylindrical structures subjected to steady uniform flow is presented in this article.
1,368 citations
Cites background from "Fluctuating lift on a circular cyli..."
...Measurements during the past century identified the fluctuating lift in steady flow about a cylinder at rest as the most likely quantifier of the combined effect of the influencing parameters; e.g., see Norberg (2003) and references cited therein....
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...…the extension of the current understanding of the Gerrard-Bloor transition waves and their disappearance in the range of Reynolds numbers from about Re E 2x104 to 5x104 (Bloor, 1964; Bloor and Gerrard, 1966; Gerrard, 1978; Zdravkovich, 1997; Norberg, 2003) to unsteady flows would be quite valuable....
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...5 ~ 1 0 ~ (see also, Bloor and Gerrard, 1966; Gerrard, 1978; Wei and Smith, 1986; Unal and Rockwell, 1988; Ahmed and Wagner, 2003; Zdravkovich, 1997, 2003; Norberg, 2003)....
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TL;DR: In this paper, the authors investigate the near wake of a cylinder at values of Reynolds number corresponding to the onset and development of shear-layer instabilities and show that the flow structure is notably altered.
Abstract: We investigate the near wake of a cylinder at values of Reynolds number corresponding to the onset and development of shear-layer instabilities. By combining quantitative experimental imaging (particle image velocimetry, PIV) and direct numerical simulations at Re = 3900/4000 and 10000, we show that the flow structure is notably altered. At higher Reynolds number, the lengths of both the wake bubble and the separating shear layer decrease substantially. Corresponding patterns of velocity fluctuations and Reynolds stress contract towards the base of the cylinder. The elevated values of Reynolds stress at upstream locations in the separated layer indicate earlier onset of shear-layer transition. These features are intimately associated with the details of the shear-layer instability, which leads to small-scale vortices. The simulated signatures of the shear-layer vortices are characterized by a broadband peak at Re = 3900 and a broadband high spectral-density 'plateau' at Re=10000 in the power spectra. The shear-layer frequencies from the present direct numerical simulations study agree well with previous experimentally measured values, and follow the power law suggested by other workers.
279 citations
Cites background or result from "Fluctuating lift on a circular cyli..."
...‡ Author to whom correspondence should be addressed: gk@dam.brown.edu Zdravkovich (1990), Szepessy & Bearman (1992), Lin, Towfighi & Rockwell (1995), Williamson (1996) and Norberg (2003)....
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...However, the lift coefficient from the computation is much lower than the experimental values (Norberg 2003)....
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TL;DR: In this article, the effect of the Reynolds number on vortex shedding was investigated for a cylinder undergoing free vibrations, and it was shown that the effect is very significant for VIVs.
269 citations
TL;DR: In this paper, the authors study the transverse vortex-induced vibrations of an elastically mounted rigid cylinder in a fluid flow and employ a technique to accurately control the structural damping, enabling the system to take on both negative and positive damping.
Abstract: In the present work, we study the transverse vortex-induced vibrations of an elastically mounted rigid cylinder in a fluid flow. We employ a technique to accurately control the structural damping, enabling the system to take on both negative and positive damping. This permits a systematic study of the effects of system mass and damping on the peak vibration response. Previous experiments over the last 30 years indicate a large scatter in peak-amplitude data ($A^*$) versus the product of mass–damping ($\alpha$), in the so-called ‘Griffin plot’.
255 citations
Cites methods from "Fluctuating lift on a circular cyli..."
...In the case of the stationary cylinder in a flow, a compilation of lift coefficient (CL) data by Norberg (2003) shows a substantial increase in CL values over the Re range from 1000 to 200 000....
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References
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Book•
01 Jan 1971
TL;DR: A revised and expanded edition of this classic reference/text, covering the latest techniques for the analysis and measurement of stationary and nonstationary random data passing through physical systems, is presented in this article.
Abstract: From the Publisher:
A revised and expanded edition of this classic reference/text, covering the latest techniques for the analysis and measurement of stationary and nonstationary random data passing through physical systems. With more than 100,000 copies in print and six foreign translations, the first edition standardized the methodology in this field. This new edition covers all new procedures developed since 1971 and extends the application of random data analysis to aerospace and automotive research; digital data analysis; dynamic test programs; fluid turbulence analysis; industrial noise control; oceanographic data analysis; system identification problems; and many other fields. Includes new formulas for statistical error analysis of desired estimates, new examples and problem sets.
6,693 citations
TL;DR: Krystek as discussed by the authors provides a comprehensive and self-contained overview of random data analysis, including derivations of the key relationships in probability and random-process theory not usually found to such extent in a book of this kind.
Abstract: This is a new edition of a book on random data analysis which has been on the market since 1966 and which was extensively revised in 1971. The book has been a bestseller since. It has been fully updated to cover new procedures developed in the last 15 years and extends the discussion to a broad range of applied fields, such as aerospace, automotive industries or biomedical research. The primary purpose of this book is to provide a practical reference and tool for working engineers and scientists investigating dynamic data or using statistical methods to solve engineering problems. It is comprehensive and self-contained and expands the coverage of the theory, including derivations of the key relationships in probability and random-process theory not usually found to such extent in a book of this kind. It could well be used as a teaching textbook for advanced courses on the analysis of random processes. The first four chapters present the background material on descriptions of data, properties of linear systems and statistical principles. They also include probability distribution formulas for one-, two- and higher-order changes of variables. Chapter five gives a comprehensive discussion of stationary random-process theory, including material on wave-number spectra, level crossings and peak values of normally distributed random data. Chapters six and seven develop mathematical relationships for the detailed analysis of single input/output and multiple input/output linear systems including algorithms. In chapters eight and nine important practical formulas to determine statistical errors in estimates of random data parameters and linear system properties from measured data are derived. Chapter ten deals with data aquisition and processing, including data qualification. Chapter eleven describes methods of data analysis such as data preparation, Fourier transforms, probability density functions, auto- and cross-correlation, spectral functions, joint record functions and multiple input/output functions. Chapter twelve shows how to handle nonstationary data analysis, classification of nonstationary data, probability structure of nonstationary data, calculation of nonstationary mean values or mean square values, correlation structures of nonstationary data and spectral structures of nonstationary data. The last chapter deals with the Hilbert transform including applications for both nondispersive and dispersive propagation problems. All chapters include many illustrations and references as well as examples and problem sets. This allows the reader to use the book for private study purposes. Altogether the book can be recommended for practical working engineers and scientists to support their daily work, as well as for university readers as a teaching textbook in advanced courses. M Krystek
3,390 citations
"Fluctuating lift on a circular cyli..." refers background or methods in this paper
...For high Reynolds numbers and when following the amplitude and frequency in time, utilizing the Hilbert transform (Bendat and Piersol, 1984), it was found that high lift-related amplitudes in general were coupled to shedding frequencies lower than the mean value. For lower Re; lower than about 6 10; there was no such apparent coupling; see also Norberg (1989). Conceivably, it takes longer time to generate the lift-related von K! arm! an vortices within periods of strong vortex shedding....
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...For Reo6 10; approximately, the lift-related PDFs were similar to those of a sine wave with random noise (two peaks) whereas for higher Re the PDFs were more like that of a narrow band, random noise function (one peak), see Bendat and Piersol (1984). In Fig....
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...A straight line at an angle 451 from the horizontal would mean two signals which are perfectly anti-correlated, whereas two completely random and independent functions would produce a circular distribution with its highest peak at the origin (Bendat and Piersol, 1984)....
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...For high Reynolds numbers and when following the amplitude and frequency in time, utilizing the Hilbert transform (Bendat and Piersol, 1984), it was found that high lift-related amplitudes in general were coupled to shedding frequencies lower than the mean value....
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...Based on repeated measurements and error analysis of Bendat and Piersol (1984), the uncertainty in the reported correlation coefficients was estimated to be 70:02 (70:01 for absolute correlation levels higher than 0....
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TL;DR: A review of wake vortex dynamics can be found in this article, with a focus on the three-dimensional aspects of nominally two-dimensional wake flows, as well as the discovery of several new phenomena in wakes.
Abstract: Since the review of periodic flow phenomena by Berger & Wille (1972) in this journal, over twenty years ago, there has been a surge of activity regarding bluff body wakes. Many of the questions regarding wake vortex dynamics from the earlier review have now been answered in the literature, and perhaps an essential key to our new understandings (and indeed to new questions) has been the recent focus, over the past eight years, on the three-dimensional aspects of nominally two-dimensional wake flows. New techniques in experiment, using laser-induced fluorescence and PIV (Particle-Image-Velocimetry), are vigorously being applied to wakes, but interestingly, several of the new discoveries have come from careful use of classical methods. There is no question that strides forward in understanding of the wake problem are being made possible by ongoing three- dimensional direct numerical simulations, as well as by the surprisingly successful use of analytical modeling in these flows, and by secondary stability analyses. These new developments, and the discoveries of several new phenomena in wakes, are presented in this review.
3,206 citations
Book•
01 Jan 1977TL;DR: In this paper, the authors focus on applications for offshore platforms and piping; wind-induced vibration of buildings, bridges, and towers; and acoustic and mechanical vibration of heat exchangers, power lines, and process ducting.
Abstract: This book focuses on applications for offshore platforms and piping; wind-induced vibration of buildings, bridges, and towers; and acoustic and mechanical vibration of heat exchangers, power lines, and process ducting. Numerous examples drive home the reality of the practical problems encountered here. More than 200 figures and 20 tables complement the text by providing such data as damping factors, lift coefficients, and the formulas needed to apply practical methods directly to a wide range of structures, from heat exchangers to hypersonic aircraft. Devoted to the analysis and prediction of flow-induced vibrations, this volume will prove of immense interest to mechanical, civil, nuclear, marine, structural, and electrical engineers; physicists, designers, and naval architects; and people working in the construction and petroleum industries, power plants, power transmission, ship building, nuclear power, energy production, and defense engineering.
1,759 citations
01 Mar 1953
TL;DR: In this article, the authors investigated the wake development behind circular cylinders at Reynolds numbers from 40 to 10,000 in a low-speed wind tunnel and found that in the stable range the vortex street has a periodic spanwise structure.
Abstract: Wake development behind circular cylinders at Reynolds numbers from 40 to 10,000 was investigated in a low-speed wind tunnel. Standard hotwire techniques were used to study the velocity fluctuations. The Reynolds number range of periodic vortex shedding is divided into two distinct subranges. At R = 40 to 150, called the stable range, regular vortex streets are formed and no turbulent motion is developed. The range R = 150 to 300 is a transition range to a regime called the irregular range, in which turbulent velocity fluctuations accompany the periodic formation of vortices. The turbulence is initiated by laminar-turbulent transition in the free layers which spring from the separation points on the cylinder. This transition first occurs in the range R = 150 to 300. Spectrum and statistical measurements were made to study the velocity fluctuations. In the stable range the vortices decay by viscous diffusion. In the irregular range the diffusion is turbulent and the wake becomes fully turbulent in 40 to 50 diameters downstream. It was found that in the stable range the vortex street has a periodic spanwise structure. The dependence of shedding frequency on velocity was successfully used to measure flow velocity. Measurements in the wake of a ring showed that an annular vortex street is developed.
1,082 citations