Evolving Structure of Tip-Vortex Generated by Helicopter Rotor Blade in a Hover

ORAL

Abstract

In a hover the vortex trail forms a helical trace with respect to the vertical rotor hub axis, and the slip stream becomes contracted rather drastically within one revolution of rotor blade, making the angular momentum of the tip vortex grow quickly. And, as wake age grows, tip vortex experiences diffusion, distortion and stretching during its evolving process. Vortex diffusion proceeds continuously just after matured until disappeared, but distortion and stretching eventuates far downstream with both being correlated. At this stage the helical trace cannot be maintained. Two bladed rotor provides information about vortex distortion as well as diffusion within one revolution of both blades with simplicity. This system makes it possible to observe the change of vortex structure before and after 180 degrees of wake age within one revolution of blade. It is naturally expected that tip vortex affected by the second blade may experience the distortion including the vortex diffusion. This paper aimed primarily to investigate change of vortex structures without and with the second blade effect by the use of experimental devices. It was resulted that tip vortices generated by the first blade satisfy Landgrebe's model of their locations even after they were accelerated by the second blade in downstream. Swirl velocity components follow Vatistas' n=2 model on both regions without loss of vortex circulation.

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Authors

  • Yong Oun Han

    Yeungnam University

  • Ivan Marusic

    Department of Organismic and Evolutionary Biology, Harvard University, School of Engineering and Applied Sciences, Harvard University, Georgia Institute of Technology, Nanyang Technological University, University of Minnesota, Kyoto University, Universit\`a degli Studi di Trieste, Eindhoven University of Technology, University of Washington, Fachbereich Physik, Philipps-Universit\"at Marburg, Germany, Department of Science and Technology, University of Twente, The Netherlands, Department of Physics, The Chinese University of Hong Kong, Hong Kong, Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China, University of Malaga (Spain), Virginia Polytechnic Institute and State University, Experimental and Computational Laboratory for the Analysis of Turbulence (ECLAT), King's College London, Strand, London WC2R 2LS, UK, Hokkaido University, Texas A&M University, California Institute of Technology, United Technologies Research Center, Center for Turbulence Research, Stanford University, Stanford, CA 94305, Georgia Tech, Imperial College, Stevens Institute of Technology, Duke University, Orbital Technologies Corporation, University College London, Oxford University, University College London (UCL), Cornell University, Yale University, PUC-Rio, Laboratoire Mati\`ere et Syst\` emes Complexes, UMR 7057 CNRS \& Un iversit\'e Paris Diderot, Paris, France, Laboratoire Physico-chimie des Polym\`eres et Milieux Dispers\'es, UMR 7615 CNRS, ESPCI, Paris, France, University of Illinois at Chicago, Harvard Medical School, INRIA Rocquencourt, Illinois Institute of Technology, Purdue University, Defence Science and Technology Organisation, Stanford University, University of Melbourne, Poznan University of Technology, Northeastern University, Berlin Institute of Technology, University of Colorado, University of California, Santa Barbara, University of California, Berkeley, National Institute for Aquatic Resources, Technical University of Denmark, Department of Physics and Center for Fluid Dynamics, Technical University of Denmark, Brown University, University of Connecticut Health Center, Univ. of Texas at Austin, University of Cambridge, Technische Universitaet Darmstadt, Darmstadt, Germany, Iowa State University, NYU, Dept Phys, Ctr Soft Matter Res, New York, NY 10003 USA, Aix Marseille Univ U1, IUSTI, CNRS, UMR Polytech Marseille 6595, F-13453 Marseille 13, France, DAMTP, University of Cambridge, Russian Academy of Sciences, Irkutsk, Technion, Faculty of Aerospace Engineering, Seattle University, DIAS, University of Naples Federico II, Orsay Maths Department, CNRS, Paris-Sud 11 University (France), Ecole Polytechnique, Kangnung National University, NJIT, Los Alamos National Laboratory, UNC Charlotte, University of Maryland, NASA-JPL, MIT, University of Wisconsin-Madison, University of Mississippi, University of Michigan, Tennessee Technological University, Carnegie Mellon University, Benjamin Levich Institute, University of Texas at Austin, University of Delaware, Purdue University, West Lafayette, The University of Western Australia, Virginia Tech, University of South Carolina, University of Twente, National Cheng Kung University, University of Michigan - Department of Biomedical-Engineering, Kuwait University, Clarkson University, Bucknell University, Center for Turbulence Research, Stanford University, Department of the Mechanical Engneeing, Shizuoka University, University of California, San Diego, Princeton University, Harvard Medical School, Harvard University, Seoul National University, University of Notre Dame, University of New Hampshire, Olin College, Brigham Young University, RWTH Aachen, Department of Physics, IREAP and IPST, University of Maryland, Department of Physics and IREAP, University of Maryland, University of Maryland College Park, School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, Technische Physik, Universitaet des Saarlandes, 66041 Saarbruecken, Rensselaer Polytechnic Institute, Southern Methodist University, University of Arizona, TU Darmstadt (Germany), TU Darsmtadt (Germany), Harvey Mudd College, University of Nottingham, University of Sevilla, University of Malaga, Imperial College London, University of Illinois at Urbana-Champaign, George Washington University, Johns Hopkins University, Syracuse University, U. S. Army ARDEC, LANL, University of Utah, Politechnica Madrid, The City College of the City University of New York, U of Wisconsin River Fall, Nagoya Institute of Technology, Japan, Massachusetts Institute of Technology, Harvard University, University of Maryland, College Park, St. Anthony Falls Laboratory, University of Minnesota, The State University of New York at Buffalo, University of Buffalo, SUNY, Department of Materials Science and Engineering University of Tennessee, Knoxville, TN, Department of Mathematics, New Jersey Institute of Technology, Newark, NJ, Instituto de F\'isica Arroyo Seco, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000, Tandil, Argentina, The University of New Mexico, Division of Mechanical and Space Engineering, Hokkaido University, Department of Mechanical Engineering, Osaka University, Sandia National Laboratories, Binghamton University, UCSB, UC San Diego, Laocharoensuk, Arizona State University, Ben-Gurion University of the Negev, Institut fuer Theoretische Physik I, Ruhr-Universitaet Bochum, NASA Langley Research Center, United States Naval Academy, University of California, Los Angeles, CNRS, University of Massachusetts Amherst, ESPCI and Ecole polytechnique, Paris, France, Lyderic Bocquet, Université de Lyon, City College of New York, Wesleyan University, Lehigh University, Kyushu Institute of Technology, IMFT, Universite de Toulouse, France, Pennsylvania State University, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, Department of Mechanical Engineering, National University of Singapore, Stony Brook University, Petroleum Institute, Department of Mechanics and Aeronautics,University of Rome ``La Sapienza'', Linne Flow Centre, KTH Mechanics, Stockholm, Department of Physics, Michigan Technological University, Department of Mechanical Engineering. University of Washington, The University of Tokyo, The Johns Hopkins University, Purdue University, West Lafayette, IN 47909, Physics of Fluids, University of Twente, The Netherlands, School of Engineering and Applied Sciences, Harvard University, Cambridge, USA, McGill University, Univ. Calif. at Davis, University of Louisville, University of Puerto Rico at Mayaguez, Tokyo Institute of Technology, Laboratoire J.-A. Dieudonne, Universite de Nice Sophia Antipolis, France, Dipartimento di Fisica Generale, Universit\`a di Torino, Italy, Institut Pasteur, Paris, France, ICTP, Auburn University, Northwestern University, University Magdeburg, St. Anthony Falls Laboratoy, Department of Civil Engineering, University of Minnesota, Department of Mechanical Engineering, University of Minnesota, International Centre for Theoretical Physics - University of Maryland, University of Maryland and Texas A\&M, International Centre for Theoretical Physics, NTNU, St. Anthony Falls Lab, University of Minnesota, Escuela T\'ecnica Superior de Ingenieros Aeron\'auticos, UPM (Madrid, Spain), Department of Physics, Ochanomizu University, Samsung Engineering Co. Ltd., Harvard Univ., Penn. State Univ., A*STAR Institute of High Performance Computing, Rutgers University, RWTH Aachen University, Xi'an Jiaotong University, Okayama University, Osaka University, London, UK, Manchester, UK, FLAIR, Dept of Mechanical and Aerospace Engineering, Monash University, Australia, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK, University of Colorado at Boulder, Oregon State University, UCL, Queen's University Canada, Delft University of Technology, DLR Goettingen, Scripps Institution of Oceanography, University of California, San Diego, Sports Aerodynamics Consultant, Mountain View, California, Mechanical Engineering, Johns Hopkins University, New Mexico State University, Clark University, University of North Carolina at Charlotte, Earth and Planetary Science, University of California - Berkeley, St. Anthony Falls Laboratory, Civil Engineering, University of Minnesota, Florida Atlantic University, JHU/APL, Université Catholique de Louvain, Belgium, Monash University, Ritsumeikan University, Japan, Michigan State University, ANL, Ship Scientific Research Center of China, Wuxi, 214082, Department of Mechanical Engineering, University of South Carolina, Columbia, SC, USA, University of Toronto, Konkuk University, Seoul, Korea, Seoul National University, Seoul, Korea, NASA Glenn Research Center, Royal Military College of Canada, University of Vermont, Mechanical and Aerospace Engineering, Cornell University, Leibniz Institute for Tropospheric Research, NCAR, CNRM; CNRS-GAME, Universit\'e de Toulouse, IMFT, University of British Columbia, Institut Jean le Rond D'Alembert, UMR 7190, Universit\'e Pierre et Marie Curie, Paris, Imperial College London, UK, KTH Mechanics, Stockholm, Sweden, University of Montenegro, Universidad Nacional Autonoma de Mexico, James Franck Institute, University of Chicago, Institute of Applied Mechanics, National Taiwan University, Clemson University, Colorado State University, The University of North Carolina, Chapel Hill, Dynaflow, Inc., University of Wisconsin, PMMH, ESPCI / LadHyx, Polytechnique, Insitutec, New York University, Dept. of Plant and Microbial Biology, U.C. Berkeley, Department of Organismal Biology, Harvard University, Department of Mathematics, University of California, Berkeley, Caltech, The Ohio State University, University of Southampton UK, Queen's University, Kingston, Canada, University of Illinois

  • Ivan Marusic

    Department of Organismic and Evolutionary Biology, Harvard University, School of Engineering and Applied Sciences, Harvard University, Georgia Institute of Technology, Nanyang Technological University, University of Minnesota, Kyoto University, Universit\`a degli Studi di Trieste, Eindhoven University of Technology, University of Washington, Fachbereich Physik, Philipps-Universit\"at Marburg, Germany, Department of Science and Technology, University of Twente, The Netherlands, Department of Physics, The Chinese University of Hong Kong, Hong Kong, Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China, University of Malaga (Spain), Virginia Polytechnic Institute and State University, Experimental and Computational Laboratory for the Analysis of Turbulence (ECLAT), King's College London, Strand, London WC2R 2LS, UK, Hokkaido University, Texas A&M University, California Institute of Technology, United Technologies Research Center, Center for Turbulence Research, Stanford University, Stanford, CA 94305, Georgia Tech, Imperial College, Stevens Institute of Technology, Duke University, Orbital Technologies Corporation, University College London, Oxford University, University College London (UCL), Cornell University, Yale University, PUC-Rio, Laboratoire Mati\`ere et Syst\` emes Complexes, UMR 7057 CNRS \& Un iversit\'e Paris Diderot, Paris, France, Laboratoire Physico-chimie des Polym\`eres et Milieux Dispers\'es, UMR 7615 CNRS, ESPCI, Paris, France, University of Illinois at Chicago, Harvard Medical School, INRIA Rocquencourt, Illinois Institute of Technology, Purdue University, Defence Science and Technology Organisation, Stanford University, University of Melbourne, Poznan University of Technology, Northeastern University, Berlin Institute of Technology, University of Colorado, University of California, Santa Barbara, University of California, Berkeley, National Institute for Aquatic Resources, Technical University of Denmark, Department of Physics and Center for Fluid Dynamics, Technical University of Denmark, Brown University, University of Connecticut Health Center, Univ. of Texas at Austin, University of Cambridge, Technische Universitaet Darmstadt, Darmstadt, Germany, Iowa State University, NYU, Dept Phys, Ctr Soft Matter Res, New York, NY 10003 USA, Aix Marseille Univ U1, IUSTI, CNRS, UMR Polytech Marseille 6595, F-13453 Marseille 13, France, DAMTP, University of Cambridge, Russian Academy of Sciences, Irkutsk, Technion, Faculty of Aerospace Engineering, Seattle University, DIAS, University of Naples Federico II, Orsay Maths Department, CNRS, Paris-Sud 11 University (France), Ecole Polytechnique, Kangnung National University, NJIT, Los Alamos National Laboratory, UNC Charlotte, University of Maryland, NASA-JPL, MIT, University of Wisconsin-Madison, University of Mississippi, University of Michigan, Tennessee Technological University, Carnegie Mellon University, Benjamin Levich Institute, University of Texas at Austin, University of Delaware, Purdue University, West Lafayette, The University of Western Australia, Virginia Tech, University of South Carolina, University of Twente, National Cheng Kung University, University of Michigan - Department of Biomedical-Engineering, Kuwait University, Clarkson University, Bucknell University, Center for Turbulence Research, Stanford University, Department of the Mechanical Engneeing, Shizuoka University, University of California, San Diego, Princeton University, Harvard Medical School, Harvard University, Seoul National University, University of Notre Dame, University of New Hampshire, Olin College, Brigham Young University, RWTH Aachen, Department of Physics, IREAP and IPST, University of Maryland, Department of Physics and IREAP, University of Maryland, University of Maryland College Park, School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, Technische Physik, Universitaet des Saarlandes, 66041 Saarbruecken, Rensselaer Polytechnic Institute, Southern Methodist University, University of Arizona, TU Darmstadt (Germany), TU Darsmtadt (Germany), Harvey Mudd College, University of Nottingham, University of Sevilla, University of Malaga, Imperial College London, University of Illinois at Urbana-Champaign, George Washington University, Johns Hopkins University, Syracuse University, U. S. Army ARDEC, LANL, University of Utah, Politechnica Madrid, The City College of the City University of New York, U of Wisconsin River Fall, Nagoya Institute of Technology, Japan, Massachusetts Institute of Technology, Harvard University, University of Maryland, College Park, St. Anthony Falls Laboratory, University of Minnesota, The State University of New York at Buffalo, University of Buffalo, SUNY, Department of Materials Science and Engineering University of Tennessee, Knoxville, TN, Department of Mathematics, New Jersey Institute of Technology, Newark, NJ, Instituto de F\'isica Arroyo Seco, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000, Tandil, Argentina, The University of New Mexico, Division of Mechanical and Space Engineering, Hokkaido University, Department of Mechanical Engineering, Osaka University, Sandia National Laboratories, Binghamton University, UCSB, UC San Diego, Laocharoensuk, Arizona State University, Ben-Gurion University of the Negev, Institut fuer Theoretische Physik I, Ruhr-Universitaet Bochum, NASA Langley Research Center, United States Naval Academy, University of California, Los Angeles, CNRS, University of Massachusetts Amherst, ESPCI and Ecole polytechnique, Paris, France, Lyderic Bocquet, Université de Lyon, City College of New York, Wesleyan University, Lehigh University, Kyushu Institute of Technology, IMFT, Universite de Toulouse, France, Pennsylvania State University, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, Department of Mechanical Engineering, National University of Singapore, Stony Brook University, Petroleum Institute, Department of Mechanics and Aeronautics,University of Rome ``La Sapienza'', Linne Flow Centre, KTH Mechanics, Stockholm, Department of Physics, Michigan Technological University, Department of Mechanical Engineering. University of Washington, The University of Tokyo, The Johns Hopkins University, Purdue University, West Lafayette, IN 47909, Physics of Fluids, University of Twente, The Netherlands, School of Engineering and Applied Sciences, Harvard University, Cambridge, USA, McGill University, Univ. Calif. at Davis, University of Louisville, University of Puerto Rico at Mayaguez, Tokyo Institute of Technology, Laboratoire J.-A. Dieudonne, Universite de Nice Sophia Antipolis, France, Dipartimento di Fisica Generale, Universit\`a di Torino, Italy, Institut Pasteur, Paris, France, ICTP, Auburn University, Northwestern University, University Magdeburg, St. Anthony Falls Laboratoy, Department of Civil Engineering, University of Minnesota, Department of Mechanical Engineering, University of Minnesota, International Centre for Theoretical Physics - University of Maryland, University of Maryland and Texas A\&M, International Centre for Theoretical Physics, NTNU, St. Anthony Falls Lab, University of Minnesota, Escuela T\'ecnica Superior de Ingenieros Aeron\'auticos, UPM (Madrid, Spain), Department of Physics, Ochanomizu University, Samsung Engineering Co. Ltd., Harvard Univ., Penn. State Univ., A*STAR Institute of High Performance Computing, Rutgers University, RWTH Aachen University, Xi'an Jiaotong University, Okayama University, Osaka University, London, UK, Manchester, UK, FLAIR, Dept of Mechanical and Aerospace Engineering, Monash University, Australia, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK, University of Colorado at Boulder, Oregon State University, UCL, Queen's University Canada, Delft University of Technology, DLR Goettingen, Scripps Institution of Oceanography, University of California, San Diego, Sports Aerodynamics Consultant, Mountain View, California, Mechanical Engineering, Johns Hopkins University, New Mexico State University, Clark University, University of North Carolina at Charlotte, Earth and Planetary Science, University of California - Berkeley, St. Anthony Falls Laboratory, Civil Engineering, University of Minnesota, Florida Atlantic University, JHU/APL, Université Catholique de Louvain, Belgium, Monash University, Ritsumeikan University, Japan, Michigan State University, ANL, Ship Scientific Research Center of China, Wuxi, 214082, Department of Mechanical Engineering, University of South Carolina, Columbia, SC, USA, University of Toronto, Konkuk University, Seoul, Korea, Seoul National University, Seoul, Korea, NASA Glenn Research Center, Royal Military College of Canada, University of Vermont, Mechanical and Aerospace Engineering, Cornell University, Leibniz Institute for Tropospheric Research, NCAR, CNRM; CNRS-GAME, Universit\'e de Toulouse, IMFT, University of British Columbia, Institut Jean le Rond D'Alembert, UMR 7190, Universit\'e Pierre et Marie Curie, Paris, Imperial College London, UK, KTH Mechanics, Stockholm, Sweden, University of Montenegro, Universidad Nacional Autonoma de Mexico, James Franck Institute, University of Chicago, Institute of Applied Mechanics, National Taiwan University, Clemson University, Colorado State University, The University of North Carolina, Chapel Hill, Dynaflow, Inc., University of Wisconsin, PMMH, ESPCI / LadHyx, Polytechnique, Insitutec, New York University, Dept. of Plant and Microbial Biology, U.C. Berkeley, Department of Organismal Biology, Harvard University, Department of Mathematics, University of California, Berkeley, Caltech, The Ohio State University, University of Southampton UK, Queen's University, Kingston, Canada, University of Illinois