构造多向局部人工透射边界的加权平均法

Weighted Average Method for Constructing Multi Directional Local Transmitting Boundaries

提出用加权平均法将边界节点附近的入射波表示为一系列预定入射角的平面波的加权叠加，以克服由于采用单一透射方向假定而导致离散局部透射边界和旁轴边界缺乏透射大角度入射波能力的缺点。根据这一思想建立的多向局部人工透射边界，能够在入射角范围内清除或减少人工边界的影响。用一个算例说明了本方法的可行性及有效性。

A new method to express the incident waves near boundary nodes by the sum of plane waves at predetermined incident angles is proposed to eliminate the shortcomings of extrapolation boundary method and para axial approximation method due to the assumption of single transmitting direction. Multi directional local transmitting boundaries are set up to eliminate or avoid the detrimental effects of the boundaries over the entire range of the incident angles. Numerical examples are given and compared with the previous results to demonstrate the feasibility and effectiveness of the method.