地球物理学报
地毬物理學報
지구물이학보
2010年
2期
401-410
,共10页
曹正良%杜栓平%周士弘%王方勇
曹正良%杜栓平%週士弘%王方勇
조정량%두전평%주사홍%왕방용
声散射%平面海底%球体目标%T矩阵方法%复像方法
聲散射%平麵海底%毬體目標%T矩陣方法%複像方法
성산사%평면해저%구체목표%T구진방법%복상방법
Acoustic scattering%Planar seabed%Spherical target%T matrix method%Complex images method
根据目标声散射的T矩阵方法、将界面附近点源激发的声场利用复像方法展开、并考虑到界而对散射声场的影响,建立了平面海底界面上方日标的声散射模型.与已有模型相比,该模型能够计算更一般情况点源激发的三维声散射场.通过计算考察基于复像方法的有关系数证明了该模型的准确性,并给出了不同入射方向的界面上刚性球体和弹性球壳的散射卢场算例,对目标散射幅度的分布以及随角度的变化规律做了分析.最后,设计实验对该模型做了验证.
根據目標聲散射的T矩陣方法、將界麵附近點源激髮的聲場利用複像方法展開、併攷慮到界而對散射聲場的影響,建立瞭平麵海底界麵上方日標的聲散射模型.與已有模型相比,該模型能夠計算更一般情況點源激髮的三維聲散射場.通過計算攷察基于複像方法的有關繫數證明瞭該模型的準確性,併給齣瞭不同入射方嚮的界麵上剛性毬體和彈性毬殼的散射盧場算例,對目標散射幅度的分佈以及隨角度的變化規律做瞭分析.最後,設計實驗對該模型做瞭驗證.
근거목표성산사적T구진방법、장계면부근점원격발적성장이용복상방법전개、병고필도계이대산사성장적영향,건립료평면해저계면상방일표적성산사모형.여이유모형상비,해모형능구계산경일반정황점원격발적삼유성산사장.통과계산고찰기우복상방법적유관계수증명료해모형적준학성,병급출료불동입사방향적계면상강성구체화탄성구각적산사로장산례,대목표산사폭도적분포이급수각도적변화규률주료분석.최후,설계실험대해모형주료험증.
A model of acoustic scattering from spherical target above a planar seabed is advanced to a condition of irradiation by a point source, with both of T matrix method and complex images method. Compared to the model of Fawcett and Lim, this model could be used to calculate scattering field from a target above a planar interface in three dimension space. Comparing some coefficients by complex images method with that by analytical formula or numerical quadrature, the computing method of the model is examined to be efficient and accurate. In addition, numerical examples of a rigid sphere and an elastic spherical shell are compared for scattering field from the target on a fluid seabed, and the scattering field dependent angle is investigated from the different grazing angle of incident wave. In order to verify the model, an experiment is carried out to measure scattered field received by vertical array in laboratory. Data are analyzed and compared with calculated results.