Numerical simulation on acoustic insulation performance of a periodic nonaxisymmetry groove structure

In order to eliminate the collar waves,a sound-isolated structure grooved on the drill collar is designed,and the 3-Dimensional finite element method has been applied to numerically investigate the insulation of the grooved structure.The results show that the sound insulation effects of the grooved structure are decided by the radius,interval and number of the grooves,and the proper grooved structure can effectively attenuate the collar mode-wave in logging while drilling environments.The attenuation of the isolator with length of 1 m can reach 22 dB,but the attenuation effect relating to the flexural waves is not obvious.