钻井液离心机关键部件内部流场及冲蚀磨损特性研究

Study on the internal flow field and erosion wear characteristics of key components of drilling fluid centrifuge

摘要:

钻井液固液分离过程中，钻屑等固相颗粒会对离心机关键部件造成严重的磨损失效与动平衡失稳，影响分离效果，缩短使用寿命。基于稠密离散相（DDPM）模型和RNG k-ε湍流模型模拟了钻井液离心机内部流场特性。结合Finnie冲蚀模型预测了关键部件的冲蚀磨损性能。探究关于转鼓转速、颗粒浓度以及介质黏度对部件冲蚀磨损性能的影响。结果表明，冲蚀主要集中在进料腔附近的螺旋输送器叶片以及转鼓锥部至沉淀出口处。随着转鼓转速的增加，离心机各部件的冲蚀速率升高。颗粒浓度的提升会加剧各部件的冲蚀。此外，介质黏度增加会降低转鼓内壁的冲蚀，但会加剧螺旋壁冲蚀。研究结果为了解离心机的冲蚀磨损特性提供了有价值的见解，并为在实际应用中优化离心机的运行和维护提出了建议。

Abstract:

During the solid-liquid separation of drilling fluids， solid-phase particles such as drill cuttings will cause serious wear failure and dynamic balance instability to the key components of the centrifuge， affecting the separation effect and shortening the service life. The internal flow field characteristics of the drilling fluid centrifuge are simulated based on the dense discrete phase model （DDPM） and the RNG k-ε turbulence model. The erosive wear performance of key components was predicted in combination with the Finnie erosion model. The effects of rotational speed， particle concentration， and medium viscosity on the erosion wear performance of the components were explored. The results show that the erosion is mainly concentrated on the blades of the screw conveyor near the feed cavity and at the bowl cone. The erosion rate of the centrifuge components rises as the rotational speed increases. Elevated particle concentration exacerbates the erosion of the components. While erosion on the inner wall of the bowl is reduced by an increase in medium viscosity， screw wall erosion is intensified. The research results provide valuable insights into the erosive wear characteristics of centrifuges and recommendations for optimizing the operation and maintenance of centrifuges in practical applications.