摘要
The propagation of multipole modal waves along the well-axis in a fluid-filled borehole surrounded by elastic and nonelastic, infinite and finite formation is analysed by using the wave equations. The phase velocity dispersion and the excitation curves are numerically calculated. The waveforms excited by attenuating bursts are also calculated. The measurements with long-spaced dipole transducers made of PZT thin disks vibrating in bending mode are carried out in a concrete model well and the experimental results are compared with the theoretical results.
The propagation of multipole modal waves along the well-axis in a fluid-filled borehole surrounded by elastic and nonelastic, infinite and finite formation is analysed by using the wave equations. The phase velocity dispersion and the excitation curves are numerically calculated. The waveforms excited by attenuating bursts are also calculated. The measurements with long-spaced dipole transducers made of PZT thin disks vibrating in bending mode are carried out in a concrete model well and the experimental results are compared with the theoretical results.
基金
The Project is supported by:Science and Technology Committee of Jiangsu Province,the Oil and Research Center of Nanjing Universitya and the Fundation of the National Education Commission