具有波阻抗不连续特性的粘弹性介质中的逆散射问题

在时间域内讨论了粘弹性介质的逆散射问题,其中粘弹性介质的波阻抗在远离入射波作用面一侧的交界面上是不连接的。介质的散射算子,传播算子所满足的微分积分方程可以用来反演未知的粘弹性介质的松弛模量,文中给出的反演过程只须利用介质层一侧的反射算子在一个走时来回的时间内的实验测量数据。最后,给出了数值算例,计算结果表明,利用方法可以较准确的反演得到材料松弛模量。

Inverse Problem for the Viscoelastic Medium with Discontinuous Wave Impedance

In this paper, the inverse problem for the viscoelastic medium is investigated in the time domain, in which the wave impedance of the medium is discontinuous at the rear interface. The differentio_integral equations governing the behavior of the scattering and propagation operators are utilized to reconstruct the relaxation modulus of the viscoelastic medium. A new approach, in which only the one_side measurement reflection data for one round trip through the viscoelastic layer, is developed. The numerical examples are given at the end of the paper. It is shown that the curves of the reconstructed moduli coincide very well with the original relaxation moduli.