Parameter influence analyses of IBC active control on rotor BVI noise based upon an integrated CFD/CSD/FW-Hpds method

An integrated CFD/CSD/FW-Hpds method is established to investigate the individual blade control (IBC) technique for reducing rotor blade-vortex interaction (BVI) noise. Based on this integrated method, the main BVI noise, i.e., the medium-frequency noise of UH-60A rotor in an oblique descending flight can be reduced by more than 10 dB with the IBC control. The sound pressure level (SPL) of the BVI noise can get a reduction of more than 7 dB by selecting the reasonable IBC control inputs. The BVI noise can be effectively enervated in various flight conditions such as different flight trajectories, especially with a descent angle of 10°.