Influence of Acoustic Media on Vibration of Submerged Cylindrical Shell with Finite Depth

From the view of sound-structure interaction, a dynamic model is built for a finite cylindrical shell submerged with finite depth below the free surface. With consideration of free surface and hydrostatic pressure, mdoal added mass concept is proposed to reveal influence of the free surface and hydrostatic pressure on the structural vibration. Some conclusions are made: presence of the free surface will make negative contribution to the modal added mass and results in the increase of coupled modal frequency; the free surface effect will be reduced and finally negligible if the immersion depth is more than 4R, ; account of hydrostatic pressure will reduce flexural stiffness of submerged structures; effect of hydrostatic pressure will be important and the shell will be instability, if the immersion depth is big enough. When the immersion depth is more than 18 meters, the effect of hydrostatic pressure cannot be neglected. © 2019, Editorial Office of Ship Building of China. All right reserved.