Study of the hydraulic disturbance suppression of a vibrator under high-frequency vibration based on experiments and numerical simulations

Abstract

Hydraulic disturbance of a vibrator is the main cause of distortion of the vibroseis geophysical exploration signal that is caused by high-frequency fluid vibration during servo valve cavity commutation. This disturbance is closely related to the structure, size, and arrangement of the hydraulic flow path of the vibrator reaction mass. In this work, a vibrator disturbance–suppression mechanism was examined, an experimental study was carried out on an improved design of the hydraulic flow channel, and the source of the hydraulic disturbance of the horizontal channel vibrator was determined. The vibrator hydraulic flow channel was changed to a vertical flow channel in the piston rod. In addition, the structure of the track was designed, and the angle of the oil inlet of the piston rod was tested at 0°, 45°, and 90°. Then, the fluid flow state and fluid–solid coupling analysis method were used to improve the vibration-suppression effect of the vibrator. The results showed that the optimal oil inlet angle is 90°, for which the turbulent intensity of the oil inlet is the smallest, the pressure drop loss is reduced, and the influence of the oil flow on the piston rod deformation is minimal. The vibration reaction mass test of the vibrator showed that the disturbance inhibition rate of the piston rod with a 90° inlet structure design reaches 64.087%; the hydraulic disturbance had the best suppression effect and effectively reduced the distortion of the seismic prospecting signals with this oil inlet angle, improving the quality and efficiency of oil and gas exploration.