METHOD AND DEVICE FOR GENERATING WAVE FIELD AT INJECTOR BOTTOMHOLE WITH AUTOMATIC TUNING OF GENERATION RESONANT MODE Russian patent published in 2015 - IPC E21B43/25 E21B28/00 B06B1/20 F15B21/12 

FIELD: oil and gas industry.

SUBSTANCE: group of inventions is related to the oil producing industry and intended for the improvement of oil recovery of productive formations. The method for generating a wave field at an injector bottomhole with the automatic tuning of a generation resonant mode lies in the generation of pressure fluctuations in a fluid flow pumped to a productive formation through tubing strings by its pumping through the flow-excited Helmholtz resonator (FEHR). At that the respective flow rate and the FEHR volume is maintained at the cross-section of a feed nozzle. Moreover the respective flow rate at the cross-section of the feed nozzle and the FEHR volume is maintained due to the movement of its downstream rare bottom, thus increasing the FEHR volume at a reduced flow rate and reduced FEHR volume at an increased flow rate. The device used to this end consists of FEHR installed inside the tubing string; it represents a hollow cylindrical chamber with flat bottoms. In the front chamber of the bottom the feed nozzle is mounted and a discharge outlet with sharp edges is made at the rare bottom. At that the rare bottom is made movable and inside the tubing string behind FEHR there is a fixed hydraulic cylinder with a spring-supported piston connected by a rod to the movable rare bottom. At that the cavity inside the hydraulic cylinder in front of the piston is connected downstream to the inner volume of the tubing string while the cavity behind the piston is communicated to the annular space.

EFFECT: improved efficiency to maintain the stable high intensity of the wave field at the bottomhole.

4 cl, 2 dwg