Optimal Design of the Linkage Between Two Downhole Hydrocyclones in Series

Downhole Oil/Water Separating System is the key technology to bring the produced fluid with 90% water cut or more from reservoir to the ground. Hydrocyclone is widely used as the downhole separator to separate oil from the produced fluid before water’s reinjection into the reservoir. Hydrocyclone can obtain high separating efficiency with a simple structure. Two hydrocyclones used in series is the new hot spot about the technology of downhole separation but it is limited for wildly use by the relatively small wellbore diameter. Two hydrocylones used in series can assure perfect separation of the oil outlet and the water outlet. The design and its optimal improvement are presented in this paper of the linkage between the water outlet of the first hydrocyclone and the inlet of the second one. Some experiments based on CFD would show its function is presented in this paper as the path between the two hydrocyclones and as the rotary of the second separator.