A methodology is presented for the prediction of those blade-dynamics/wake-vorticity interactional effects responsible of the so-called B VI noise. Specifically, flapping and pitching motion of rigid blades of rotors in incompressibl e potential flow is addressed. The blade dynamics is integrated by using two different techniques: (i) a time-accurate modified Newmark-/? approach, and (ii) a "flip-flop" technique that consists of alternating aerodynamic and dynamic periodic analyses. Aerodynamic loading are evaluated by a free-wake boundary-element approach. Numerical results are presented to show the capability of the methodology introduced to capture aeroelastic BVI effects. Specifically, the equivalence between the two time-integration approaches, and discuss the advantages and disadvantages of each of them. The importance of the free-wake aerodynamic model in the blade dynamics analysis is investigated, with particular attention on the influence on the aeroelastic BVI effects.
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