Research On The Suppression Effect Of Gradient U-shaped Grooves On The Drilling Collar Wave Generated By The Impulse Sound Source Deep Detection While Drilling

Drilling acoustic logging technology is an advanccd technology serving the field of oil cxploration,one cmerging development directions is drilling impulse source depth detection technology,impulse sound sources with large frequency bandwidths are used in depth-while-drilling instruments,it can cffcctively improve the detection accuracy and detection distance.Since the impulse sound source is a monopole sound source,which will excite drill collar mode waves when working.Drill collar waves can seriously interfere with formation wave information,therefore suppressing drill collar waves is an urgent problem to solve.In this paper,a new gradient U-shaped method is proposed to design sound insulation,and the sound insulation effcct of drill collar waves was studied.Using ANSYS finite element software.finite element simulation was used to analyze the safety and acoustic characterization of the drill collar acoustic body model.Firstly,the influence of differet parameters on the safety performance of the sound insulation is analyzed,and the geometric parameters that meet the mechanical strength of the drill collar are selected for further acoustic characteristic analysis.Secondly,the influence of different notch parameters on acoustic characteristics of U-shaped notch sound insulation was discussed,and the sound insulation performance of gradient groove width sound insulation was mainly evaluated.The simulation results show that the gradient groove width sound insulation obtained on the 7-inch drill collar sound insulation model has more sound attenuation,wider sound barrier band range and more stable sound attenuation coefficient curve than a single groove width sound insulator,indicating,that the gradient groove has a better suppression effect on the drill collar wave than the traditional single groove width sound insulator.Al this time,the sound insulation frequency bandwidth and the sound attenuation coefficient are large,and the suppression ability of the drill collar mode wave is good and the safety meets the conditions.