Abstract: Behaviors of the wake of an axisymmetric bluff body and its control by means ofacoustic forcing have been experimentally investigated for Reynolds numbers ranging from 3.0 χ10~3to 1.0 χ10~5.According to flow visualization, the flow separates at the rear of model, and the evolution ofseparated shear layer finally results in the belieal vortices shedding and forming the reverse flow.The length of recirculation region increases from Re = 3.0 χ 10~3 to Re = 2.0χ10~4, and remains aconstant of X_r/D = 0.975 in Re...