| Gas anchor is one kind of important downhole equipment for deep well pump production system, especially for high gas oil ratio oil wells. The separation efficiency of anchor will effect pump efficiency and well yield directly. Gas anchor separation mechanism and separation efficiency are studied first in this paper. The structural property and operating principle of different kinds of gas anchor are then researched. Through the analysis of fluid velocity field and stress acting on gas bubble, simplified bubble separation mathematical model is fetched, and theoretical separation efficiency equation is trial developed. In order to realize flow field numerical analogue calculation of oil gas separator, on the base of gas-fluid two-phase flow, a three-dimensional flow model for different anchors is established in which liquid phase is continuous phase, and gas phase is dispersed phase. Relevant control equation set and equation discretization method were also confirmed. The gas-liquid turbulent flow in gravity anchor and helical anchor is simulated with CFD software FLUENT. After fluid flow field distribution situation in the two types of anchor is obtained, sensitivity analysis is made to describe the effects of anchor structural parameter and operation parameter on separation efficiency. The simulation results and theoretical analysis about flow field distribution regular in gas anchor are relatively closed, which shows that the theoretical model could essentially describe the course oil gas separation. This study provides certain foundation for the structural and operation parameters design and optimizing.
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