摘要
变化地形声场计算是越来越经常碰到的情况。变化地形往往给声场计算带来计算量增大、求解精度下降的问题。坐标系选择是声场计算中非常重要的问题,该文研究基于地形的合适正交曲线坐标系选取规则。在此坐标系中求解Helmholtz方程,能够极大简化求解过程,提高计算精度。结合简正波理论,从新的角度展示了正交曲线坐标系在某些典型变化地形线源声场计算问题中的应用。对于几种典型的海洋声波导问题,可以利用合适的曲线坐标系简化问题,给出更直观的物理图像。
Sound field computations with non-flat sea floor are more and more popular now. Variation of sea floor brings problems like increasing calculation quantity or reducing the accuracy. Selection of coordinate system in sound field computation is very important. In the paper, we study the selection method of suitable coordinate system based on topography, which can improve computation accuracy and reduce calculation load greatly. Combined with normal modes theory, we show applications of orthogonal curvilinear coordinates in sound field computation with some typical non-flat sea floor and line source from a new perspective. For several typical problems of ocean acoustic waveguide, we can simplify the problem by using suitable curvilinear coordinate system and give more intuitive physical images.
引文
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