中国物理B ›› 2023, Vol. 32 ›› Issue (3): 34301-034301.doi: 10.1088/1674-1056/ac8e98

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Response characteristics of drill-string guided wave in downhole acoustic telemetry

Ao-Song Zhao(赵傲耸)1,2, Hao Chen(陈浩)1,2,3,†, Xiao He(何晓)1,2,3, Xiu-Ming Wang(王秀明)1,2,3, and Xue-Shen Cao(曹雪砷)1,3   

  1. 1 State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Beijing Engineering Research Center of Sea Deep Drilling and Exploration, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2022-04-25 修回日期:2022-07-29 接受日期:2022-09-02 出版日期:2023-02-14 发布日期:2023-02-14
  • 通讯作者: Hao Chen E-mail:chh@mail.ioa.ac.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11734017 and 12174421), and the Scientific Instrument Developing Project of the Chinese Academy of Sciences (Grant Nos. YJKYYQ20200072 and GJJSTD20210008).

Response characteristics of drill-string guided wave in downhole acoustic telemetry

Ao-Song Zhao(赵傲耸)1,2, Hao Chen(陈浩)1,2,3,†, Xiao He(何晓)1,2,3, Xiu-Ming Wang(王秀明)1,2,3, and Xue-Shen Cao(曹雪砷)1,3   

  1. 1 State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Beijing Engineering Research Center of Sea Deep Drilling and Exploration, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2022-04-25 Revised:2022-07-29 Accepted:2022-09-02 Online:2023-02-14 Published:2023-02-14
  • Contact: Hao Chen E-mail:chh@mail.ioa.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11734017 and 12174421), and the Scientific Instrument Developing Project of the Chinese Academy of Sciences (Grant Nos. YJKYYQ20200072 and GJJSTD20210008).

摘要: Modeling of a drill-string acoustic channel has been an important topic in downhole telemetry for a long time. The propagation of drill-string guided waves in the borehole contains excitation, attenuation, and mode conversion issues that have not been considered by existing modeling methods. In this article, we formulate a hybrid modeling method to investigate the response characteristics of a fundamental-mode drill-string wave in various borehole environments. This hybrid method provides channel functions, including transmitting and receiving deployments, periodicity of the structure, and formation property changes. The essential physics of the drill-string wave propagation is captured with a one-dimensional model. The analytical solutions of the wavefield in multilayered cylindrical structures are introduced into a propagation matrix to express drill-string-wave interactions with the borehole environments. The effectiveness of the proposed method is confirmed through comparison with the finite-difference method. In addition, by designing numerical models, we investigate the conversion effect of the drill-string wave at the tool joint. We demonstrate that the conversion intensity of the drill-string wave is positively correlated not only with the cross-sectional area of the tool joint but also with the wave impedance of the outer formation. Hard formation outside the borehole reduces the energy leakage while intensifying the conversion of drill-string waves to Stoneley waves, and the opposite is true for the drill string in an infinite fluid. The converted Stoneley waves interfere with the drill-string waves, resulting in variations of bandgap distribution, which challenges the reliability of the data transmission.

关键词: downhole acoustic telemetry, drill-string wave, bandgap characteristic, mode conversion

Abstract: Modeling of a drill-string acoustic channel has been an important topic in downhole telemetry for a long time. The propagation of drill-string guided waves in the borehole contains excitation, attenuation, and mode conversion issues that have not been considered by existing modeling methods. In this article, we formulate a hybrid modeling method to investigate the response characteristics of a fundamental-mode drill-string wave in various borehole environments. This hybrid method provides channel functions, including transmitting and receiving deployments, periodicity of the structure, and formation property changes. The essential physics of the drill-string wave propagation is captured with a one-dimensional model. The analytical solutions of the wavefield in multilayered cylindrical structures are introduced into a propagation matrix to express drill-string-wave interactions with the borehole environments. The effectiveness of the proposed method is confirmed through comparison with the finite-difference method. In addition, by designing numerical models, we investigate the conversion effect of the drill-string wave at the tool joint. We demonstrate that the conversion intensity of the drill-string wave is positively correlated not only with the cross-sectional area of the tool joint but also with the wave impedance of the outer formation. Hard formation outside the borehole reduces the energy leakage while intensifying the conversion of drill-string waves to Stoneley waves, and the opposite is true for the drill string in an infinite fluid. The converted Stoneley waves interfere with the drill-string waves, resulting in variations of bandgap distribution, which challenges the reliability of the data transmission.

Key words: downhole acoustic telemetry, drill-string wave, bandgap characteristic, mode conversion

中图分类号:  (General linear acoustics)

  • 43.20.+g
91.60.Lj (Acoustic properties) 47.11.Bc (Finite difference methods)