Prediction of vibration and sound radiation of the underwater complex shell-structure by SEA-ST

Because the statistical energy analysis (SEA) has many merits to solve the questions of vibration and sound radiation of the complex shell-structure in high frequency. When these merits of statistical energy analysis and similitude theory (ST) are combined, vibration and sound radiation of the complex shell-structure which is the ring-stiffened cylindrical shell with hemi-spherical shell on the ends are studied by SEA-ST The whole studied system is divided in eight subsystems, and the SEA physical model and power flow equations among these subsystems are established. The similitude relationships of input power, coupling loss factor and modal density of the subsystems between the prototype and its scaled-down model are analyzed. According to the similitude (ST) and power flow balance equation, when the immerged shell-structure are excited, the similar relations of spatially averaged vibration response and the underwater radiation sound power are established for prototype and its scaled-down model. In the end, the experimental results of vibration and sound radiation of prototype are good agreement with the predicted results of its scaled-down model.