Calculation of Bistatic and Monostatic Scattering from Underwater Target with an Hybridization of the Finite and Boundary Element Methods by an Adaptative Absorbing Boundary Condition

Estimates of the target strength of objects in all phases of the design of coastal security systems are very important. Numerical techniques for predicting this data for a given submarine class are under continuous development around the world. This article presents an efficient way to calculate bistatic and monostatic scattering indicators from large-scale underwater targets using a hybridization of the Finite and Boundary Element Methods including an adaptive absorbing boundary condition. This approach enables a considerable reduction of the computational time for a fast estimation of target strength values with very good accuracy, taking advantage of the strengths of both numerical methods through a domain decomposition technique. The simulation results show that the proposed method can be used to calculate significant bistatic and monostatic scattering from underwater targets like a submarine up to the mid-frequency range.