Critical gas velocity prediction for vortex drainage gas wells

Critical gas velocity prediction for vortex drainage gas wells

Zhao ZhangRuiquan Liao Peng Fu Yubin Su Wei Luo Dingxue Zhang 

Petroleum Engineering College, Yangtze University, Wuhan 430100, China

Laboratory of Multiphase Pipe Flow, Gas Lift Innovation Center, CNPC, Wuhan 430100, China

Research Institute of Oil and Gas Technology, PetroChina Changqing Oilfield Branch Company, Xi’an 710021, China

Corresponding Author Email:
8 March 2018
| |
6 July 2018
| | Citation



This paper attempts to disclose the law of critical gas velocity in the swirling flow field induced by the vortex tools. For this purpose, a critical gas velocity calculation model for vortex drainage gas wells was established based on the axial force balance between the liquid film and the gas core in swirling flow, and modified with the experimental data in previous studies. Then, the effects of helix angle and hub diameter of vortex tool on the reduction amplitude of critical gas velocity were analyzed by comparing the modified model with Turner model. Through experimental verification, it is learned that our new model can predict the critical gas velocity under different production conditions with different vortex tools. The reduction amplitude of critical gas velocity increased with the helix angle and decreased with the growth in hub diameter. The reduction amplitude ranged from 55.03% to 59.35% as the helix angle varied from 15 ° to 75 ° and the hub diameter varied from 34mm to 50 mm. The helix angle has a greater impact than the hub diameter on the reduction amplitude. The research findings shed new light on the design and application of the vortex tools.


gas well, vortex tool, drainage gas recovery, critical gas velocity, swirling flow, friction factor, prediction model, reduction amplitude

1. Introduction
2. Prediction Model for Critical Gas Velocity in Swirling Flow
3. Model Evaluation and Results Discussion
4. Field Test
5. Conclusions

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