Helicopter active noise suppression device integrating sound array and on-propeller control

A helicopter active noise suppression device integrating a sound array and on-propeller control, comprising an annular loudspeaker array, a plurality of force exciters, an error microphone, an Active Noise Cancellation (ANC) controller, a cockpit sensor, and an airborne computer, wherein the annular loudspeaker array is arranged on an outer side of a rotor hub above a fuselage;

• the force exciters are installed at blade trailing edges of a helicopter;
• the plurality of force exciters are installed at the trailing edge of each blade;
• both the airborne computer and the cockpit sensor are installed inside a helicopter cockpit;
• the ANC controller is respectively connected with the annular loudspeaker array and the error microphone;
• and the airborne computer is respectively connected with the cockpit sensor and the error microphone;
• the plurality of force exciters are configured for generating force noise in an reversed phase to thickness noise;
• the plurality of force exciters are further configured for reducing rotor load noise and suppressing blade-vortex interaction noise;
• a noise radiation sphere database is stored in the airborne computer;
• the noise radiation sphere database includes a set of noise radiation spheres about flight speed, a set of noise radiation spheres about a tension coefficient, a set of noise radiation spheres about an angle of attack of a rotor disc, and a set of noise radiation spheres about tip speed;
• the cockpit sensor is configured for acquiring real-time flight parameters of the rotor;
• the flight parameters include the flight speed, the tension coefficient, the angle of attack of the rotor disc, and the tip speed;
• the airborne computer is configured for obtaining noise radiation spheres corresponding to the flight parameters according to the flight parameters and the noise radiation sphere database, and projecting the noise radiation spheres to an area to be subjected to noise reduction, so as to obtain the noise of the area to be subjected to noise reduction;
• sound field characteristics corresponding to the flight parameters are stored on a spherical surface of the noise radiation sphere;
• the error microphone is configured for transferring an error vector between a noise control target and the noise of the area to be subjected to noise reduction to the ANC controller;
• and the ANC controller is configured for controlling, according to the error vector, the annular loudspeaker array to generate noise in an reversed phase to the error vector.