Physics of Fluids 20, 010401 ͑2008͒

PHYSICS OF FLUIDS 20, 010401 ͑2008͒

Editorial: Fifty years of Physics of Fluids John Kim1 and L. Gary Leal2 1Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, California 90095-1597, USA 2Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93106, USA ͑Received 13 December 2007; published online 31 January 2008͒

͓DOI: 10.1063/1.2832366͔

I. THE PAST 50 YEARS two five-year periods ͑1998–2002 and 2003–2007͒. We rec- Physics of Fluids began publication in January, 1958, as ognize that citations are only one measure of a paper’s im- a journal devoted to original contributions covering kinetic pact, and we also recognize that citations for the preceding theory, statistical mechanics, structure, and general physics year or two have little chance of being listed even in a list of of gases, liquids, and other fluids. The journal was initiated the past five years. The fact that citations build up gradually to meet the needs of the Division of Fluid Dynamics of the is a characteristic of our field, and of the lasting value of the American Physical Society ͑APS͒. In the inaugural issue of research. The subjects of these most-highly-cited papers il- Physics of Fluids, the chairman of the governing board of the lustrate the impact of Physics of Fluids on a wide variety of American Institute of Physics ͑AIP͒ and the president of the topics, and is also indicative of the evolution of subject mat- APS remarked that publication of Physics of Fluids was ter over the years from a journal that was heavily oriented unique in that the members of a division had a vital interest toward plasma physics in the early days to its current status in, and constituted a driving force for, the initiation of the as a journal that publishes broadly across the field of fluid journal. mechanics. The original scope of the journal, as noted by the Found- An important characteristic of Physics of Fluids is that ing Editor François Frenkiel, included ionized fluid and we recognize the need for rapid dissemination of new re- plasma physics, as well as basic aspects of the physics of search results and, thus, we have reduced significantly the fluids. The journal eventually split into two journals in 1989, time taken from submission to acceptance by improving our Physics of Fluids A and Physics of Fluids B. Then, in 1994, review process. In 2006, the average time from submission Physics of Fluids A became Physics of Fluids and Physics of to acceptance was 22 weeks. Papers are now published on- Fluids B became Physics of Plasmas. In this issue, the read- line first as they become available. The look and contents of ers will find some highlights of 50 years of publication in an the journal have also evolved significantly as new technolo- invited article written by John Scott, who retired in 1997 as gies have become available. Authors can display their figures Journal Publisher after 30 years of service at AIP. in color—free of charge—in the electronic version of the Physics of Fluids has grown significantly, as is evident journal. We have also added a multimedia capability that from the number of papers published over the years ͑see allows authors to display their animated movies, with a di- Table I͒, and the number of papers submitted, which has rect click-on access from the online article. All past issues more than doubled in the past decade. are available and searchable from our website. All these new The journal has also evolved from a mainly-American features have made the journal a valuable resource for au- journal to one that now serves the international thors and readers. community—70% of papers received in 2006, for example, The journal benefited tremendously from the Founding were from outside the United States. This is also reflected in Editor, François Frenkiel, whose visionary mind recognized the current makeup of the Board of Associate Editors, listed the need for a high-quality journal devoted to a special topic at http://pof.aip.org. of physics, and from the Distinguished Editor, Andreas Ac- Articles from Physics of Fluids have had a significant rivos, who established Physics of Fluids as one of the best impact on fluids dynamics research through publication of journals for fluid mechanics research. Frenkiel’s contribu- high-quality papers. A listing of the ten most-cited papers tions have been recognized by the Division of Fluid Dynam- during each of the first four decades of publication is shown ics ͑DFD͒ Frenkiel Award, which is given annually to a in Table II, along with the ten most-cited papers in the past young author of a paper that had been published in Physics

TABLE I. Numbers of papers published in Physics of Fluids.

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

344 363 371 397 352 315 344 419 458 505 480 543

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TABLE II. Most-cited papers, 1958–31 December 2007.

Title Authors Physics of Fluids

1958–1967

1 Numerical calculation of time-dependent viscous incompressible H. Harlow and J. E. Welch 8͑12͒, 2182 ͑1965͒ flow of fluid with free surface 2 Finite-resistivity instabilities of a sheet pinch H. P. Furth, J. Killeen, and M. N. Rosenbluth 6͑4͒,459͑1963͒ 3 Inertial ranges in two-dimensional turbulence R. H. Kraichnan 10͑7͒, 1417 ͑1967͒ 4 Inertial-range spectrum of hydromagnetic turbulence R. H. Kraichnan 8͑7͒,1385͑1965͒ 5 A perturbation theory for strong plasma turbulence T. H. Dupree 9͑9͒,1773͑1966͒ 6 Velocity space diffusion from weak plasma turbulence C. F. Kennel and F. Engelman 9͑12͒, 2377 ͑1966͒ in a magnetic field 7 Collisionless damping of nonlinear plasma oscillations T. Oneil 8͑12͒, 2255 ͑1965͒ 8 Stability of liquid flow down an inclined plane C. S. Yih 6͑3͒,321͑1963͒ 9 Longitudinal ion oscillations in a hot plasma B. D. Fried and R. W. Gould 4͑1͒,139͑1961͒ 10 Velocity distributions in molecular beams from nozzle sources J. B. Anderson and J. B. Fenn 8͑5͒,780͑1965͒

1968–1977

1 Parametric-instabilities of electromagnetic waves in plasmas J. F. Drake, P. K. Kaw, Y. C. Lee, G. Schmidt, C. S. Yue, 17͑4͒,778͑1974͒ and M. N. Rosenbluth 2 Nonlinear growth of tearing mode P. H. Rutherford 16͑11͒, 1903 ͑1973͒ 3 Theory of stimulated scattering processes D. W. Forslund, J. M. Kindel, and E. L. Lindman 18͑8͒, 1002 ͑1975͒ in laser-irradiated plasmas 4 Nonlinear, three-dimensional magnetohydrodynamics H. R. Strauss 19͑1͒,134͑1976͒ of noncircular tokamaks 5 Fluid-dynamics of relativistic blast waves R. D. Blandford and C. F. McKee 19͑8͒, 1130 ͑1976͒ 6 Transport equations in turbulence B. J. Daly and F. H. Harlow 13͑11͒, 2634 ͑1970͒ 7 Small-scale structure of a scalar ﬁeld convected by turbulence R. H. Kraichnan 11͑5͒,945͑1968͒ 8 Plasma transport in toroidal conﬁnement systems M. N. Rosenbluth, F. L. Hinton, and R. D. Hazeltin 15͑1͒,116͑1972͒ 9 Tearing mode in cylindrical tokamak H. P. Furth, P. H. Rutherford, and H. Selberg 16͑7͒, 1054 ͑1973͒ 10 Kinetic processes in plasma-heating by resonant mode A. Hasegawa and L. Chen 19͑12͒,1924͑1976͒ conversion of Alfven wave

1978–1987

1 Equation of motion for a small rigid sphere M. R. Maxey and J. J. Riley 26͑4͒,883͑1983͒ in a nonuniform ﬂow 2 Pseudo-three-dimensional turbulence in magnetized A. Hasegawa and K. Mima 21͑1͒,87͑1978͒ nonuniform plasma 3 Magnetic reconnection via current sheets D. Biskamp 29͑5͒, 1520 ͑1986͒ 4 Self-focusing of short intense pulses in plasmas G. Z. Sun, E. Ott, Y. C. Lee, and P. Guzdar 30͑2͒,526͑1987͒ 5 Coulomb solid of small particles in plasmas H. Ikezi 29͑6͒, 1764 ͑1986͒ 6 Externally driven magnetic reconnection and a powerful T. Sato and T. Hayashi 22͑6͒, 1189 ͑1979͒ magnetic energy converter 7 Coherent structures—reality and myth A. K. M. F. Hussain 26͑10͒,2816͑1983͒ 8 An electron conductivity model for dense plasmas Y. T. Lee and R. M. More 27͑5͒, 1273 ͑1984͒ 9 Self-consistent growth rate of the Rayleigh-Taylor instability H. Takabe, K. Mima, L. Montierth, and R. L. Morse 28͑12͒,3676͑1985͒ in an ablatively accelerating plasma 10 Nonlinear behavior and turbulence spectra of drift waves A. Hasegawa, C. G. Maclennan, and Y. Kodama 22͑11͒, 2122 ͑1979͒ and Rossby waves

1988–1997

1 A dynamic subgrid-scale eddy viscosity model M. Germano, U. Piomelli, P. Moin, and W. H. Cabot 3͑7͒,1760͑1991͒a 2 A proposed modification of the Germano-subgrid-scale D. K. Lilly 4͑3͒,633͑1992͒a closure method 3 Three-dimensional optimal perturbations in viscous shear-flow K. M. Butler and B. F. Farrell 4͑8͒,1637͑1992͒a 4 Development of turbulence models for shear flows by a double V. Yakhot, S. A. Orszag, S. Thangam, T. B. Gatski, 4͑7͒,1510͑1992͒a expansion technique and C.G. Speziale 5 A dynamic subgrid-scale model for compressible turbulence P. Moin, K. Squires, W. Cabot, and S. Lee 3͑11͒, 2746 ͑1991͒a and scalar transport 6 A new quotidian equation of state ͑QEOS͒ for hot dense matter R. M. More, K. H. Warren, D. A. Young, and G. B. Zimmerman 31͑10͒,3059͑1988͒b

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TABLE II. ͑Continued.͒

Title Authors Physics of Fluids

7 A general classification of three-dimensional flow-fields M. S. Chong, A. E. Perry, and B. J. Cantwell 2͑5͒,765͑1990͒a 8 Direct numerical simulations of the turbulent mixing V. Eswaran and S. B. Pope 31͑3͒,506͑1988͒b of a passive scalar 9 A constitutive equation for concentrated suspensions R. J. Phillips, R. C. Armstrong, R. A. Brown, A. L. Graham, 4͑1͒,30͑1992͒a that accounts for shear-induced particle migration and J. R. Abbott 10 A dynamic mixed subgrid-scale model and its application Y. Zang, R. L. Street, and J. R. Koseff 5͑12͒, 3186 ͑1993͒a to turbulent recirculating flows

1998–2002

1 Direct numerical simulation of turbulent channel flow R. D. Moser, J. Kim, and N. N. Mansour 11͑4͒,943͑1999͒ up to Retau =590 2 Scaling laws in granular flows down rough inclined planes O. Pouliquen 11͑3͒,542͑1999͒ 3 Electrospinning and electrically forced jets. I. Stability theory M. M. Hohman, M. Shin, G. Rutledge, and M. P. Brenner 13͑8͒, 2201 ͑2001͒ 4 The formation and evolution of synthetic jets B. L. Smith and A. Glezer 10͑9͒, 2281 ͑1998͒ 5 Electrospinning and electrically forced jets. II. Applications M. M. Hohman, M. Shin, G. Rutledge, and M. P. Brenner 13͑8͒, 2221 ͑2001͒ 6 Optimal disturbances and bypass transition in boundary layers P. Andersson, M. Berggren, and D. S. Henningson 11͑1͒,134͑1999͒ 7 Filtered density function for large eddy simulation P. J. Colucci, F. A. Jaberi, P. Givi, and S. B. Pope 10͑2͒,499͑1998͒ of turbulent reacting flows 8 On a three-dimensional volume tracking model M. Bussmann, J. Mostaghimi, and S. Chandra 11͑6͒, 1406 ͑1999͒ of droplet impact 9 An approximate deconvolution procedure S. Stolz and N. A. Adams 11͑7͒, 1699 ͑1999͒ for large-eddy simulation 10 Experimental demonstration of a homogeneous R. Stieglitz and U. Muller 13͑3͒,561͑2001͒ two-scale dynamo

2003–2007

1 Energy dissipation rate and energy spectrum in high–resolution Y. Kaneda, T. Ishihara, M. Yokokawa, K. Itakura, and A. Uno 15͑2͒,L21͑2003͒ direct numerical simulations of turbulence in a periodic box 2 Apparent slip flows in hydrophilic C. H. Choi, K. J. A. Westin, and K. S. Breuer 15͑10͒,2897͑2003͒ and hydrophobic microchannels 3 Laminar drag reduction in microchannels using J. Ou, B. Perot, and J. P. Rothstein 16͑12͒,4635͑2004͒ ultrahydrophobic surfaces 4 A comparative study of the turbulent Rayleigh-Taylor instability G. Dimonte, D. L. Youngs, A. Dimits, S. Weber, M. Marinak, 16͑5͒, 1668 ͑2004͒ using high-resolution three-dimensional numerical simulations: S. Wunsch, C. Garasi, A. Robinson, M. J. Andrews, The Alpha-Group Collaboration P. Ramaprabhu, A. C. Calder, B. Fryxell, J. Biello, L. Dursi, P. MacNeice, K. Olson, P. Ricker, R. Rosner, F. Timmes, H. Tufo, Y. N. Young, and M. Zingale 5 Stokes’ first problem for an Oldroyd-B fluid W. C. Tan and T. Masuoka 17͑2͒, 023101 in a porous half space ͑2005͒ 6 Homotopy of exact coherent structures in plane shear flows F. Waleffe 15͑6͒, 1517 ͑2003͒ 7 Particle trapping in three-dimensional fully L. Biferale, G. Boffetta, A. Celani, A. Lanotte, and F. Toschi 17͑2͒, 021701 developed turbulence ͑2005͒ 8 Transport of bubbles in square microchannels T. Cubaud and C. M. Ho 16͑12͒,4575͑2004͒ 9 Instability of electrokinetic microchannel flows H. Lin, B. D. Storey, M. H. Oddy, C. H. Chen, 16͑6͒, 1922 ͑2004͒ with conductivity gradients and J. G. Santiago 10 A generating mechanism for apparent fluid slip D. C. Tretheway and C. D. Meinhart 16͑5͒, 1509 ͑2004͒ in hydrophobic microchannels aPhysics of Fluids A: Fluid Dynamics. bPhysics of Fluids. of Fluids during the preceding calendar year. Acrivos’s con- ourselves and also on behalf of the editors who preceded us, tributions are recognized by the APS Acrivos Award, given we would like to take this opportunity to thank you all, es- annually to the author of the best Ph.D. thesis. The lists of pecially the referees and associate editors who have contrib- recipients of both awards are shown in Tables III and IV, uted their valuable time to Physics of Fluids. respectively. The close relationship between the APS Division of The journal’s success would not have been possible Fluid Dynamics and Physics of Fluids has played a vital role without the contributions and devotions of the authors, ref- in fostering and maintaining Physics of Fluids as a preemi- erees, and associate editors. A list of all current and past nent journal for the fluid mechanics research community for associate editors is shown in Table V. As editors, both for the past 50 years. Since 1985, we have published an annual

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TABLE III. François Naftali Frenkiel Award for Fluid Mechanics. open websites. Although AIP, which is responsible for Phys- ics of Fluids and nine other peer-reviewed printed journals, is Year Recipient an active participant in the debates concerning some aspects 1984 Eric Herbolzheimer of these changes, it is not yet clear to us what the next 50 1985 John C. Neu years hold for the scientific publication process. However, 1986 Sanjiva Lele we do believe that the peer review process is still currently a 1987 Saleh Tanveer healthy and highly-valued contributor to the maintenance of 1988 Donald L. Koch high-quality published literature in our field of fluid mechan- 1989 Eric S. G. Shaqfeh ics, and we will do everything that we can to preserve this 1990 Juan C. Lasheras and Benigno J. Lazaro legacy for future generations of researchers in the field. 1991 Mingquan Cheng and Hsueh-Chia Chang As far as Physics of Fluids is concerned, we will strive 1992 Kathleen J. Stebe, Shi-Yow Lin, and Charles Maldarelli to continue to make the journal more attractive by maintain- 1993 David G. Dritschel and Darryn W. Waugh ing the high quality of papers we publish, by minimizing the 1994 Jeffrey W. Jacobs 1995 Gregory Eyink amount of time from submission to publication, by expand- 1996 Rajat Mittal and S. Balachandar ing our scope into new areas of research, and by bringing in 1997 Krishnan Mahesh new technologies from which both authors and readers can 1998 Tom Hou, John Lowengrub, and Michael Shelley benefit. 1999 Anne D. Pussaud and Sandra M. Troian As we begin the second 50 years of Physics of Fluids, 2000 Michael P. Brenner we have taken the opportunity, along with our board of as- 2001 Stefano Cerutti and Charles Meneveau sociate editors, to evaluate many aspects of the journal and to 2002 Jonathan P. Rothstein and Gareth H. McKinley think about how it should evolve in the future. One obvious 2003 Maxime Nicolas change is that the size of the journal has continued to in- 2004 Michael D. Graham crease. In the ten years that we have been the editors, the 2005 Roberto Verzicco number of submissions has more than doubled, to approxi- 2006 Jan Skotheim and L. Mahadevan mately 1100 papers in 2007. In view of this, there is a need 2007 Re’em Sari to focus on the most important contributions of the journal, and this has led to a decision to make a significant change beginning with Volume 20 ͑2008͒: we will no longer publish papers in the “Brief Communications” category. We recog- issue, the Gallery of Fluid Motion, based upon the winning nize that this change will remove a relatively unique venue entries of the poster and video contest at the annual meeting that has been used effectively by some authors for contribu- of the DFD. More recently, we have begun to publish se- lected papers based upon the Otto LaPorte Lecture and other tions of significance that do not, however, contain sufficient invited lectures at the annual meeting. material for full-length papers. However, studying the impact of these papers over the years, we found that relatively few have been cited in the subsequent literature, thus indicating II. CHANGES FOR THE NEXT 50 YEARS that relatively few have made a significant contribution to the fluid mechanics literature. At this time of increased pressure As we enter the next 50 years, it is evident that the on the journal due to the rapid increase in submission levels, scientific publishing field is undergoing many changes, it is not possible to sustain this low-impact activity. We are largely driven by the availability of new modes of commu- still happy to consider shorter papers for publication, but nication but also by the introduction of new models for pub- these will need to rise to the level of significance expected of lication. It is noteworthy that some fields of physics now all “full-length” papers in order to be accepted for publica- “publish” mainly via the posting of unrefereed papers on tion. We also continue to welcome shorter papers for our rapid publication “Letters” section. The Letters section of Physics of Fluids has been a much TABLE IV. Andreas Acrivos Dissertation Award in Fluid Dynamics. more active and vital contribution to the journal in recent Year Recipient years, due primarily to the addition of an Associate Editor for Letters, chosen from our regular group of associate editors. 2000 Vittorio Cristini The first Associate Editor for Letters was Bud Homsy in 2001 Greg A. Voth 2001 and 2002. For the past five years, this responsibility has 2002 Wade Schoppa been handled by Andrea Prosperetti. We are extremely ap- 2003 Prosenjit Bagchi preciative of the great job that these two individuals have 2004 Jacqueline Ashmore done in overseeing the upgrade in the Letters section. Begin- 2005 Silas D. Alben ning with this issue ͑January 2008͒, we welcome John Hinch 2006 Eric Lauga 2007 David Saintillan as the new Associate Editor for Letters. We hope that the Letters section of Physics of Fluids will continue to serve the

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TABLE V. Current and Past Associate Editors.

A. Acrivos H. G. Ahlstrom I. Alexeff W. P. Allis R. A. Alpher T. M. Antonsen H. Aref D. Baganoff D. E. Baldwin J. W. Beams R. P. Behringer G. Bekeﬁ R. D. Bengston D. J. Benney H. L. Berk T. H. Berlin I. B. Bernstein L. A. Berry A. Bers D. Bershader R. Betchov W. S. Bleakney C. Brennen F. G. Brickwedde R. J. Briggs O. Buneman J. M. Burgers B. J. Cantwell P. J. Catto S. Chandrasekhar F. F. Chen L. Chen H. Choi J.-M. Chomaz C. K. Chu J. D. Cole D. E. Coles B. Coppi G. M. Corcos S. Corrsin C. F. Curtiss J. S. Dahler J. Davis J. M. Dawson R. C. Di Prima R. J. Donnelly R. A. Dory W. E. Drummond H. L. Dryden J. L. Dunlap T. H. Dupree C. Eckart W. M. Elasser H. W. Emmons R. J. Emrich H. P. Eubank J. C. Evvard G. W. Ford D. W. Forslund R. G. Fowler T. K. Fowler J. P. Freidberg B. D. Fried E. A. Frieman H. P. Furth I. I. Glass J. P. Gollub M. Gottlieb R. W. Gould H. Grad M. S. Green H. R. Griem E. P. Gross R. A. Gross J. B. Grotberg G. E. Guest N. G. Hadjiconstantinou T. J. Hanratty E. G. Harris R. W. Harvey R. D. Hazeltine D. S. Henningson J. R. Herring N. Hershkowitz A. Hertzberg E. J. Hinch F. L. Hinton J. O. Hirschfelder G. M. Homsy E. Hopﬁnger H. Hornung C. W. Horton L. N. Howard A. K. M. F. Hussain H. Ikezi J. Jiminez A. Kantrowitz J. Kaplan A. N. Kaufman J. B. Keller R. E. Kelly C. F. Kennel D. W. Kerst J. M. Kindel J. G. Kirkwood A. L. Kistler P. S. Klebanoff D. L. Koch A. C. Kolb J. Koplik L. S. G. Kovasznay R. H. Kraichnan W. L. Kruer G. Kuerti A. M. Kuethe W. B. Kunkel H. Lam O. Laporte J. Laufer E. P. Lee H. W. Liepmann C. C. Lin J. R. Lister C. L. Longmire E. K. Longmire J. L. Lumley W. V. R. Malkus J. H. Malmberg J. Marshall, Jr. T. C. Marshall E. A. Mason T. Maxworthy J. E. Mayer J. C. McWilliams H. Mirels P. Moin P. Monkewitz D. Montgomery M. V. Morkovin R. L. Morse R. D. Moser H. M. Mott-Smith G. Navratil W. A. Newcomb F. T. M. Nieuwstadt S. A. Orszag S. Ostrach E. Ott J. M. Ottino E. N. Parker G. N. Patterson F. W. Perkins, Jr. H. E. Petscheck M. S. Plesset S. B. Pope R. F. Post R. S. Post A. Prosperetti E. Reshotko E. L. Resler, Jr. W. C. Reynolds F. L. Ribe B. H. Ripin J. A. Rome M. Rosenbluth A. Roshko N. Rostoker P. H. Rutherford P. G. Saffman W. Saric S. A. Schaaf G. B. Schubauer L. E. Scriven A. R. Seebass E. S. G. Shaqfeh S. F. Shen F. S. Sherman A. Simon L. Sirovich A. J. Smits L. Spitzer, Jr. K. R. Sreenivasan R. A. Stern T. H. Stix R. N. Sudan H. L. Swinney L. Talbot E. Teller R. N. Thomas D. A. Tidman C. E. Treanor A. W. Trivelpiece S. M. Troian L. Turner G. E. Uhlenbeck J. A. Van Allen G. J. F. van Heijst P. Wegener J. Weinstock H. Weitzner R. B. White S. E. Widnall D. R. Willis W. W. Willmarth T. Y. Wu J. C. Wyngaard C.-S. Yih A. Zebib

fluid mechanics community as an important outlet for short improve Physics of Fluids and to respond effectively to the papers that contain highly-significant results for which rapid changes in scientific publication that are occurring at an publication is desirable. ever-increasing pace. There are additional changes coming in the way that we We believe that Physics of Fluids is currently healthy, handle manuscripts at the point of submission and after ac- continuously growing in size, and expanding into new areas ceptance as they are transferred to AIP for publication, as we of interest. We value our collaborations with the DFD of the strive to make the whole process as convenient and timely as APS, and we look forward to continuing to serve the inter- possible. There may also be more changes in the journal as national fluid mechanics community. As we celebrate 50 we look back on the preceding 50 years and plan for the years of excellent publication, we look forward to many future. Indeed, we take this opportunity to invite all readers, more years of quality scientific publications for the fluid me- authors, or referees to provide input on ways that we can chanics research community throughout the world.

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