Abstract: Water flooding is a popular technology used for oil-displacement in middle and later period of oilfield development.The no-zzles used for water injection are cylindrical nozzles that spray continuous jet.This paper discusses how to enhance water injection rate and oil recovery efficiency using self-resonating pulsating injection method theoretically,and its feasibility in engineering.Self-resonating pulsating nozzle for water injection has been designed and tested in the laboratory. The jet velocity pulsation is determined by a hotwire anemometer.By Fourier transform the power spectral density functions of the pulsation velocity is obtained and analyzed. The result shows that the self-resonating pulsating nozzle described in the paper can spray pulsating jet of low frequency and large velocity.The maximum pulsating velocity is 78 percent of the axial average velocity.The frequency of the velocity pulsation is less than 1300 Hz.Self-resonating pulsating water flooding technology does not need to change the current injection technique and does not need any other additional equipment.The only thing we need to do is to redesign the blanking plug in a very simple way.It is very significant to increase water injection rate and oil recovery efficiency by applying the redesigned plug.

Key words: oilfield development, low frequency, fluctuation, water nozzle, water flooding, EOR

摘要： 注水驱油是油田开发中后期普遍采用的一项技术,所使用的水嘴是普通柱形喷嘴,它喷出的射流是连续射流.文中就如何利用自激波动注水来提高注水量和采收率在理论方面进行了探讨;并根据工程要求对其可行性进行了讨论,设计了自激波动注水用喷嘴,利用热线测速仪测量了射流的波动速度,对波动信号进行了谱分析.结果说明流体流过自激波动注水器能产生很强的低频波动速度,最大波动速度与轴心平均速度的比可达78%,波动频率在1300Hz以下.自激波动提高注采率技术,不需要改变现有的注水工艺流程,不需要附加任何设备,只需对堵塞器稍做改动就可以实现,对提高注采率很有意义.

关键词: 油田开发, 低频, 波动, 水嘴, 注水, 采收率