Research On Characteristics Of Directional Impulse Sound Sources In A U-shape Connected Well

U-shaped connected wells are becoming more widely used as energy demand increases.The traditional U-well connection technology mainly relies on magnetic guidance technology to connect two wells,but the magnetic guidance technology has short detection distance.In order to increase the detection distance and ensure precise communication between the two wells,a new type of acoustic wave connection technology based on the impulse sound source is proposed.In the drilling well,the directional impulse source and receiver are installed with drill collar,and the impulse sound source emits acoustic energy directionally,and the receiver on the drill collar receives the acoustic signal reflected by the target casing well.It can obtain the orientation and distance of the target casing well by analyzing the signal parameters,which contributes to guiding the drill bit to communicate with the target casing well.Therefore,it has a bright future while make a research on the characteristics of the directional impulse source while drilling in the U-shaped connected well.Firstly,it conducts an experimental study on the underwater impulse sound source and analyzes the basic characteristics of the sound source.Experiments show that the sound source generation process is short,and the sound signal has large power,high pressure and broadband frequency,even that the sound intensity can reach more than 260 dB,and it has a high electro-acoustic energy conversion efficiency.Secondly,based on the sound source convergence,it designs a reasonable energy-gathered mechanism for the sound source through COMSOL modeling and simulation analysis.Comparing and analyzing the energy of the ellipsoidal and parabolic energy-gathered mechanism and the direction of energy accumulation,it is determined that the parabolic energy-gathered mechanism is more suitable for the downhole sound source.The single-variable method is used to model the different concave depth and opening size of different p energy-gathered mechanism,and it determines the suitable size of concave depth and opening size which is working for downhole drilling.Finally,it established a directional impulse source model for drilling through the finite element software.Then it is carried out that include the sound intensity before and after the energy gathering comparison,the directivity study of the sound source and the initial detection of the U-shaped connected well in the fast and slow stratum.In summary,the impulse sound sourceis a wide-band,high-energy,high-conversion efficiency,controllable and repeatable emission source signal,which takes high sound pressure intensity,good energy-concentration effect,and orientation.