%0 Journal Article
%T Pressure feedback
%A Giorgio Graziani
%A Giovanni Bernardini
%A Massimo Gennaretti
%A Sara Modini
%J International Journal of Aeroacoustics
%@ 2048-4003
%D 2018
%R 10.1177/1475472X18774052
%X With the aim of alleviating the noise annoyance emitted by blade每vortex interactions occurring on helicopter main rotors, the present work presents a methodology suitable for the identification of a multi-cyclic harmonic controller based on the actuation of rotor blades equipped with Miniature Trailing Edge Effectors. The objective of the control methodology is the direct suppression of the aerodynamic noise sources by generation of localized high-harmonic blade每vortex interaction counter-actions. The set-up of control devices is selected on the basis of the blade每vortex interaction scenario, taking into account a trade-off between effectiveness and power requirement. The control law is efficiently identified by means of an optimal controller synthesized through suitable two-dimensional multi-vortex, parallel blade每vortex interaction problems. The proposed methodology is validated by the application to realistic helicopter main rotors during low-speed descent flights, numerically simulated through high-fidelity aerodynamic and aeroacoustic solvers based, respectively, upon a three-dimensional free-wake boundary element method to solve the potential flow around rotors in blade每vortex interaction conditions and the Farassat 1A formulation. Results concerning the capability of the proposed controller to alleviate the blade每vortex interaction noise emitted by a realistic helicopter main rotor are presented and discussed
%K Blade每vortex interaction loads
%K Blade每vortex interaction noise
%K rotor aeroacoustics
%K rotor aerodynamics
%K multi-cyclic control
%U https://journals.sagepub.com/doi/full/10.1177/1475472X18774052