螺旋形岩屑床清除工具流场数值模拟

摘要

岩屑床清除工具能够防止岩屑床形成,破坏已形成的岩屑床,有效解决水平井井眼清洁问题.许多学者开展了水平井岩屑清除技术研究,研制出不同类型的岩屑床清除工具,但在工具结构参数优化方面缺少深入研究,缺乏高效的岩屑床清除工具,制约了其进一步的开发与应用.文中设计了不同结构参数螺旋形岩屑床清除工具,通过CFD(计算流体动力学)数值模拟的方式,从叶片前后压降、切向速度、岩屑分布情况等方面分析了叶片长度、高度和叶片数对岩屑床清除工具作用效果的影响规律,为水平井岩屑床清除工具的研制与应用提供了重要的参考依据.%Cuttings bed removers,which could prevent the formation of cuttings bed and destroy the existing cuttings bed,are proved to be helpful to solve the problem of horizontal wellbore cleaning.Relevant researches are carried out and many types of cuttings bed removers are created.However,these tools are not effective enough,as vague understanding and optimization of structure parameters of cuttings bed remover limit its further development and application.In this paper,cuttings bed removers with different leaf blade length,height and number of spiral blade are designed and numerical simulation based on CFD is carried out to find out the law of drill fluid flow field near cuttings bed remover and adjacent drill strings.The effects of leaf blade length,height and number of blade are analyzed by the contrast of pressure drop before and after the blade,the tangential velocity and the distribution of cuttings.These provide important guidance and reference for the development and application of cuttings bed remover.