Measurements are presented of the flow produced by the perpendicular encounter between a streamwise vortex and a wing tip. The resulting flow field, which contains two interacting tip vortices, models the turbulence found in the near tip region on the advancing side of a helicopter rotor. This region is a significant source of BWI noise (blade-wake interaction) at level flight and mild climb conditions. Both single and two-point turbulence measurements are presented. The single-point measurements reveal the form of the turbulence structure generated by the interaction of the tip vortices. The two-point measurements reveal, in terms of wavenumber-frequency spectra, the turbulence length scales that would be encountered by a noise-generating blade cutting this flow. It is concluded that the interaction between the vortices not only winds up the wakes to which they are attached but is also a source of new organized turbulence. It is also found that wavenumber-frequency spectra measured in this flow are dominated by the large-eddies present in the turbulence and are not well modeled by assuming a homogeneous isotropic spectrum.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Turbulence structure resulting from a vortex/wing-tip encounter


    Additional title:

    Untersuchung der durch Rotorblattspitzen-Wirbel-Interaktionen erzeugten turbulenten Strukturen


    Contributors:

    Published in:

    Publication date :

    1999


    Size :

    9 Seiten, 14 Bilder, 1 Tabelle, 22 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English






    Turbulence structure resulting from a vortex/blade-tip interaction

    Wittmer, Kenneth / Devenport, William / Wenger, Christian | AIAA | 1997


    Wake Vortex Encounter Research

    Wilson, Jeffrey M. | NTRS | 1995


    ER-2 High Altitude Turbulence Encounter

    Jumper, G. / Cowley, J. / Hahn, D. et al. | British Library Conference Proceedings | 2009