A high-order based boundary condition for dynamic analysis of infinite reservoirs

An approach for modeling the radiation damping of an infinite acoustic waveguide is the high-order absorbing boundary condition. This approach is employed in this study as a basis for analysis of an infinite water channel. In order to achieve an accurate and efficient approach for this purpose, the imposed boundary condition should have two features: (a) the reservoir’s bottom absorption which highly affects the pressure distribution inside the reservoir should be included in the formulation of the ABC; (b) the far-field base excitation, which is a significant factor during the vertical excitation should also be considered in the analysis. By separating the overall hydrodynamic pressure into scattered and incident pressure and involving the scattered term in the formulation of the ABC, an accurate and versatile boundary condition is obtained. This boundary condition is then applied in the analysis of several benchmark examples and the obtained results demonstrate the efficiency of the proposed technique.

► High-order absorbing boundary condition is extended to dynamic analysis of infinite reservoirs. ► Both evanescent and propagating absorbing terms are included in the analysis. ► The unbounded reservoir bottom excitation is taken into account. ► The absorption of reservoir’s bottom is considered in the formulation of the ABC. ► By solving multiple numerical examples, the employed technique is proved to be highly accurate and efficient.