Active control of vibration and radiated noise in the shaft-shell coupled system of an underwater vehicle

Active control is effective in reducing the low-frequency vibration and acoustic radiation of the stern system of an underwater vehicle. This paper theoretically investigates the reduction of vibration and far-field radiation noise in the stern system of an underwater vehicle arising from propeller bearing forces and surface force excitations. Based on the Flügge theory and Euler–Bernoulli theory, an analytical dynamic model of the shaft-shell system is established. The effectiveness of the analytical model is verified through finite element and boundary element methods. The impact of actuator placement, error signal selection, and control strategies on the effectiveness of active control is discussed. A combined active control scheme for the shaft-shell system, involving electromagnetic actuators installed on both the shaft and the shell, is proposed. This scheme effectively controls shaft vibration, shell vibration, and far-field acoustic radiation simultaneously. The theoretical model established in this paper can be used as a reference for low-frequency vibration control of an underwater vehicle.