KMS Chongqing Institute of Green and Intelligent Technology, CAS
| Shale ultrasonic numerical simulation based on the viscoelastic medium wave theory | |
Chen, Qiao1,2 ; Xu, Fenglin1,2; Cheng, Liang3; Liu, Hong4; Jian, Xu5; Zhu, Honglin1,6; Chen, Jilong1
| |
| 2019 | |
| 摘要 | Using the ultrasonic transmission method to study the ultrasonic response characteristics of shale is the basis for the use of logging data to solve geological and engineering problems in shale gas development. However, among few literatures about such related research by present, shale has been only regarded as an elastic medium with its viscoelastic characteristics being unfortunately ignored. In view of this, based on the theory of viscoelastic medium waves, combined with the ultrasonic penetration experiments, we simulated an initial and vibration sources environment as well as boundary and stability conditions. On this basis, we made the ultrasonic transmission experiments of shale with different bedding angles by the staggered grid finite difference method. The following findings were obtained. (1) The waveform trend obtained by numerical simulation is coincided with the physical experiment result. (2) The rules of shale attenuation coefficients varied along with the test frequencies and the bedding angles obtained by numerical simulation calculation and physical experiment based on ideal and real cores agree well with each other. (3) Under a certain constant bedding size and density, the wave velocity declined in power function and the attenuation coefficient increases linearly. In conclusion, this numerical computation method proposed in this paper is scientific and reasonable and is of strong adaptability and can not only be used to analyze the influence of shale bedding characteristics on ultrasonic propagation characteristics from a microscopic point of view, but avoid human errors and save the experimental cost, therefore it is of important theoretical and practical significance. © 2019, Natural Gas Industry Journal Agency. All right reserved. |
| DOI | 10.3787/j.issn.1000-0976.2019.06.007 |
| 发表期刊 | Natural Gas Industry
 |
| ISSN | 10000976 |
| 卷号 | 39期号:6页码:63-70 |
| 收录类别 | EI |
| 语种 | 中文 |
