Guangrong Lu, Yongjun Hou*, Xianjin Wu, Hang Wu, Rui Jiang and Mingjun Du
Background: In recent years, a kind of drilling method of Solid-Liquid separation combined with pulsating vacuum formed by vibrating screen and compressed air injection has emerged in oil drilling, which greatly improves the gas, solid and liquid separation ability of the drilling fluid vibration screen.
Objective: Based on the above ideas, a kind of hydrocyclone used for gas-liquid separation with the pulsating feed boundary was proposed. The separation performance of gas-liquid hydrocyclone may change greatly due to the mixed pulsation of the gas-liquid fluid transported by the jet pump. Therefore, the flow characteristics of the pulsating feed hydrocyclone need to be analyzed and explored to provide basic data for further improvement of structure.
Methods: The development status of cyclone separators are summarized through related literatures and patents investigation. The Computational Fluid Dynamics (CFD) software ANSYS Fluent 2019 R3 is used to analyze the flow field characteristics and optimize the parameters of the hydrocyclone with stable feed. Then, programming by the User-Define-Function (UDF) of Fluent is used to simulate the flow field of the separator under the condition of pulsating feed, meanwhile, the flow field analysis and parameter optimization are carried out accordingly.
Results: The optimal parameters in stable state and pulsed state are obtained through the analysis of efficiency curve. The results show that the flow field can be stabilized in the pulsating feed state, and the sinusoidal pulsing with a frequency of 0.4Hz is used to achieve the highest separation efficiency, reaching 85.5%.
Conclusion: The separators with pulsating feed and stable feed have similar flow field characteristics, and the optimal structural parameters under pulsating feed are obtained. Compared with the stable feed condition, the pulsating feed condition can connect multiple cyclone separators, which can separate more drilling fluid in unit time, and the work efficiency could be improved. It has a strong practicability, which provides an important basis for the structure optimization in future.
Gas-liquid cyclone separator, CFD, parameters optimization, UDF, pulsating feed boundary, separation efficiency.
Department of School of Electrical and Mechanical Engineering, Southwest Petroleum University, Chengdu 610500, Department of School of Electrical and Mechanical Engineering, Southwest Petroleum University, Chengdu 610500, Department of BOMCO Chengdu Equipment Manufacturing Company, Chengdu 610052, Department of BOMCO Chengdu Equipment Manufacturing Company, Chengdu 610052, Department of Sichuan BOMCO Special Vehicle Manufacture Co.,Ltd., Guanghan 618300, Department of School of Electrical and Mechanical Engineering, Southwest Petroleum University, Chengdu 610500