弹性介质中密度ρ与拉梅常数λ、μ的衍射层析成像方法研究

STUDY OF DIFFRACTION TOMOGRAPHY METHOD FOR DENSITY ρ AND LAME COEFFICIENTS λ,μIN ELASTIC MEDIA

利用接收到的纵波信息，通过解纵波方程得到介质的密度和拉梅常数分布函数．首先，在频率波数域建立了描述入射纵波信号、接收纵波信号和介质三参数扰动量之间关系的积分方程．然后，建立了关于接收信号的各频率成份的方程组．经过正反傅氏变换求解此方程组即可得到介质三参数的分布函数．最后，就跨孔观测系统进行了数值模拟成像试验。结果表明方法有效．

On the assumption that source signal is P wave,the distribution functions of density and Lame coefficients are obtained from P wave signal by solving P wave equation.At first,integral equation is derived in frequency-wave number domain describing the relations of incident wave,received P wave and the disturbances of the three medium parameters.Then equation system is derived corresponding to various frequency components of received signal.The distribution functions of three medium parameters are obtained through solving the equation system by forward and inverse Fourier transform. At last,the results of numerical tests are given for cross0hole synthetic data.