Study of target strength of underwater vehicle

The target strength (TS) is a significant factor in the underwater stealth technology. Many studies focus on reducing the target strength to minimize detection probabilities. However, there are many factors affecting the target strength, such as the geometries and structures of vehicles, the sonic reflection coefficients, the coating material of outer hull, etc. In this paper, we present the result of target strength calculation with respect to three parameters, which are the geometry of the vehicle, the hull thickness, and frequency of incident acoustic waves. The great challenge is the demand of large memory and fast computation due to the dimensions of the vehicle with high-frequency incident acoustic waves. To solve this problem, we obtain the calculating efficiency with better computing facility and apply scaling method to the vehicle which reduce the size of the model. The target strength (TS) is calculated by finite element method (FEM) of acoustic-solid coupled model. Results show that the TS increases with increasing size of model due to increase of the ensonified area. TS decreases with reducing hull thickness of the hull. Lastly frequency would affect the TS, which is due to the excitation of different acoustic modes.