| 摘要: |
| 利用有限元数值模拟研究了由点源姐成的相控线阵声波测井辐射器对充液井孔中各种波动模式波的影响,重 点分析了阵元个数对各种波动模式波响应幅庑的影响。结果表明,随着阵元间延迟时间的增加,声束偏转角逐渐增 加。控制声束偏转角分别满足相控线阵辐射声束在纵、横波临界角位置入射时，随相控线阵阵元个数增加,折射纵、 横波响应幅度呈正比增加;在非临界角入射时，阵元个数的增加对折射纵、横波能量的增强效果不明显。当阵元个 数不变时,随声束偏转角的增加,纵、横波声压值也开始逐渐增加’且在偏转角分别等于第一或第二临界角时达到最 大;若偏转角再继续增加,声压值又会逐渐减弱。 |
| 关键词: 相控线阵声波辐射器 声波测井 有限元法 阵元个数 偏转角 |
| DOI： |
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| 基金项目:国家自然科学基金资助项目(40374049); CNPC测井重点实验室资助项目 |
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| Effects of element number of linear phased array acoustic transmitter on waves of various modes in fluid-filled borehole |
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CHEN Xue-lian1,QIAO Wen-xiao2
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(1. College of Geo-Resource and Information in China University of Petroleum, Dcmgying 257061, Shandong Province, China;2. School of Resource and Inforrmtion Technology in China University of Petroleum, Beijing 102249，China)
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| Abstract: |
| Effects of the acoustic logging transmitter of linear phased array composed of point source on waves of various modes in fluid-filled borehole were studied by finite element method (FEM). And the influence of element number of array on wave amplitude was mainly analyzed. The results show that the steered angle of acoustic arrays increases with the delay time increasing between the neighbour elements. When the angle of radiated acoustic beam steered to the critical angle of the compressional or shear wave, the amplitude of the compressional or shear wave can increase in direct ratio with the element number of the phased array. If the steered angle of radiated acoustic beam departs from the critical angle of the compressional or shear wave in other controlled delay time, the enhancement of the amplitudes is little. And when the element number is changeless, the amplitude of the ccxnpressional or shear wave can be strengthened gradually with the steered angle increasing. But when the steered angle exceeds the critical angle, the amplitude will be lowered with the steered angle increasing sequentially. |
| Key words: linear phased array acoustic transmitter acoustic logging finite element method element number of array steered angle |
