In this work, a compressible Reynolds Averaged Navier Stokes (RANS) solver is used to investigate the aerodynamics of a coaxial rotor configuration under hovering conditions; in order to evaluate the predictive capability of the computational approach and to characterize the unsteadiness in the aerodynamic flow field of a coaxial system. Compared to previous work by the authors, the present calculations use finer mesh along with smaller time step size, thereby aiding in a better capture and preservation of the wake. Additional benefits are attained from improvements in the sliding mesh boundary interpolation scheme. A trimming procedure is implemented, which allows for detailed yaw and thrust trim. The global quantities such as thrust and power are predicted reasonably well. In the torque trimmed situation, the top rotor shares significant percentage of the total thrust at lower thrust levels, which decreases to about 55 % of the total thrust at higher thrust values. The interaction between the rotor systems is seen to generate significant impulses in the instantaneous thrust and power. The characteristic signature of this impulse is explained in terms of the blade thickness (a venturi effect) and loading (an upwash-downwash effect). Further, interaction of the top-rotor wake with the blades of the bottom rotor results in low-harmonic unsteadiness. The flow field of the coaxial system is very complicated due to various blade-vortex and vortex interactions. The wake of the top rotor contracts faster compared to that of the bottom rotor because of the vortex-vortex interaction. Further, the top rotor wake converts vertically down at a faster rate due to increased inflow.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    High resolution computational investigation of trimmed coaxial rotor aerodynamics in hover


    Weitere Titelangaben:

    Hochauflösende numerische Untersuchung der getrimmten koaxialen Rotoraerodynamik im Schwebeflug


    Beteiligte:


    Erscheinungsdatum :

    2008


    Format / Umfang :

    24 Seiten, 23 Quellen



    Medientyp :

    Aufsatz (Konferenz)


    Format :

    Print


    Sprache :

    Englisch





    High Resolution Computational Investigation of Trimmed Coaxial Rotor Aerodynamics in Hover

    Lakshminarayan, V.K. / Baeder, J.D. / AHS international | British Library Conference Proceedings | 2008




    Computational Investigation of Small Scale Coaxial Rotor Aerodynamics in Hover

    Lakshminarayan, V. / Baeder, J. / American Institute of Aeronautics and Astronautics | British Library Conference Proceedings | 2009