充液井孔声场的路径积分估值中的极点应用(英文)

The application of poles in the contour integral evaluation of the wavefield in a fluid-filled borehole

针对索末菲尔德路径积分方法和垂直路径积分方法对充液井孔中的声场进行了数值模拟 ,比较了两者利用实轴积分方法计算的结果 .结果表明 :如果计算中不包括相关黎曼面上适当的复极点的贡献 ,垂直路径积分不能精确地给出声波全波列波形 ,纵波垂直路径积分也难以给出精确的纵波首波 ;但是 ,如果计算中考虑了这些极点 ,就能得到相关的正确结果 .

Numerical simulations for the wavefield in a fluid\|filled borehole are carried out for the methods of the Sommerfeld contour integration and of the vertical contour integration. The results are compared with those computed by the method of the real\|axis integration. Our results show that, if the contributions of the appropriate complex poles on related Riemann sheets are not fully included, the vertical contour integration can not accurately yield the full acoustic waveform, and also that its compressional contour integral can not always yield the compressional head arrival. Correct relevant results can, however, be obtained if these poles are considered.ericalsimulati