投球式滑套球座液-固两相流冲蚀预测及验证

PREDICTION AND VERIFICATION ON THE LIQUID-SOLID TWO-PHASE FLOW EROSION OF BALL SEAT OF THE FRACTURING SLEEVE

针对水平井投球式滑套分段压裂技术在现场施工中极易出现压裂液中固相颗粒对球座冲蚀磨损问题,文章提出在球座表面喷涂硬质合金涂层和碳化钨涂层的方法,探索球座的耐冲蚀性能;运用欧拉-拉格朗日法、浓密离散相模型和半经验冲蚀模型求解了颗粒对球座的冲蚀速率。结果表明,数值模拟能够较为精确地预测不同涂层球座冲蚀后的轮廓;与碳化钨涂层相比,硬质合金涂层更耐冲蚀,随着冲蚀时间延长,球座质量损失逐渐增加。该模型能够用于预测球座复杂流场的冲蚀,有望为球座进一步优化设计提供参考。

In view of the erosion problem of solid particles in the fracturing fluid which impact the ball seat in the horizontal well fracturing technology.In this paper,the method of spraying hard alloy coating and tungsten carbide coating on the surface of the ball seat was carried out to explore the erosion resistance of the ball seat.The Euler-Lagrange model,dense discrete phase model and semi-empirical model were applied to calculate the erosion rate of ball seat.Results show that the erosion profile of ball seat can be predicted more precisely with the use of numerical simulation.Compared with tungsten carbide coating,cemented carbide coating is more resistant to erosion,with the extension of erosion time,the mass loss of ball seats increases.This method can be applied to predict the erosion of complex flow field in ball seat,thus providing a reference for further optimization of the ball seat.