冲激声源深探测钻铤波压制声学性能研究

Research on Acoustic Performance of Deep Exploration Drill Collar Wave Suppression for Impulse Sound Source

随钻冲激声源深探测技术可以在钻井过程中同时进行地层纵横波的测量,其大功率、宽频带、高幅度的特性有助于精细探测近井带周围的裂缝分布情况。由于声源必须安装在厚壁钻铤上,会激发沿钻铤传导的钻铤波,这可能会掩盖地层信息,对随钻冲激声源深探测造成不利影响。因此,压制钻铤波成为能够有效进行随钻冲激声源深探测的关键。通过数值模拟方法,研究了随钻冲激声源深探测时刻槽方式和激发频率下隔声体的声学性能变化规律。研究结果表明,刻槽方式能够增大钻铤波的声衰减系数,在压制低频钻铤波时,采用外刻槽结构的隔声性能更优,同时声源中心激发频率也会对钻铤波的压制效果产生影响。

The deep detection technology of drilling induced sound source can simultaneously measure the longitudi-nal and transverse waves in geological formations during the drilling process.Its high power,wide frequency band,and high amplitude characteristics are conducive to finely detect the distribution of fractures near the wellbore.Due to the fact that the sound source must be installed on thick walled drill collars,it can excite drill collar waves that propagate along the drill collars,which may mask formation information and have adverse effects on the depth detection of drilling induced sound sources.Therefore,suppressing drill collar waves has become the key to effectively detecting the depth of drilling induced sound sources.By using numerical simulation methods,the acoustic performance changes of the sound insulation body under the slot mode and excitation frequency during the deep detection of drilling induced sound sources are studied.The research results indicate that the grooving method can increase the acoustic attenuation coefficient of drill collar waves.When suppressing low-frequency drll collar waves,the external grooving structure has better sound insula-tion performance.At the same time,the excitation frequency of the sound source center also affects the suppression effect of drill collar waves.