关键词: 自激波动, 喷嘴射流, 注水, 机理, 实验研究

Abstract: The working principles of nozzle with a self-excited oscillation source are introduced.The experimental results of the pressure impulse characteristics of the nozzle and the characteristics of the frequency attenuation under the ambient pressure are briefly described.The transmitting rules of the pressure fluctuation of the nozzle along the axes and the radial and the principles of water-injection with self-excited oscillation are presented.A kind of injector was designed and tested in the field.The study results show that the self-resonation cavitating jet can be used as the oscillation source of the self-excited oscillation water-injection.The oscillating pressure wave of water jet can transmit a distance more than 100 cm in radial direction and 600 cm in the axial direction.This method can improve the water injection efficiency distinctly for the reservoir with lower water subsorption during the later period due to build-up formation.The average injection pressure was reduced by 2.1 MPa,and the average volume of daily water injection for a single layer increased by 29m³.It can also prolong the water-injection time for the general water-injection well.

Key words: self-excited pulsation, self-exited oscillation nozzle, pressure impulse, water jet, water-injection mechanism, experimental study