Numerical Analysis and Reduction of Blade-Vortex Interaction (BVI) Noise in Helicopter Using Numerical Simulation

Computational Aero-acoustic (CAA) simulations on two NACA 23,012 airfoil were performed using STAR-CCM+ to study the BVI noise, and near Trailing edge air suction (TEAS) active control concept was investigated to diffuse the vortices and hence reduce BVI noise. Coupled CFD and CAA analogies were used to capture the wake and far-field noise propagation in 2D simulations. Farassat 1A formulation of Ffowcs Williams-Hawkings (FW-H) equation is used to capture the far-field pressure fluctuations. Effect of active control on the percentage reduction in vortex strength downstream and overall BVI noise is investigated.