单颗粒和双颗粒在聚丙烯酰胺溶液中沉降过程的数值模拟  

Numerical simulation on the sedimentation process of single and double particles in polyacrylamide solution

作　　者：耿明亮 王艳萍[1] 邓晓烽 祖也航 李昳[1] GENG Mingliang;WANG Yanping;DENG Xiaofeng;ZU Yehang;LI Yi(School of Mechanical Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学机械工程学院,杭州310018

出　　处：《浙江理工大学学报（自然科学版）》2024年第5期674-680,共7页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：国家重点研发计划项目(2022YFE0126600,2022YFC280150);浙江省重点研发计划项目(2022C01194)。

摘　　要：针对钻井过程中停钻工况下岩屑在钻井液中的沉降问题,以球形颗粒代替岩屑,以聚丙烯酰胺(Polyacrylamide,PAM)溶液代替钻井液,采用计算流体动力学-离散元法(Computational fluid dynamics-discrete element method,CFD-DEM)分别模拟了单颗粒和双颗粒在PAM溶液中的沉降过程,探究颗粒粒径和PAM溶液浓度对单颗粒沉降过程的影响,考察颗粒粒径和颗粒初始间距对水平排列的双颗粒沉降过程的影响,并简要分析了颗粒的受力情况。结果表明:单颗粒在PAM溶液中的沉降速度比在水中小,随粒径的增大而增大,随PAM溶液浓度的增加而减小;水平排列的双颗粒在沉降过程中受Magnus力和Saffman力的显著影响,颗粒间距越小,粒径越大,Magnus力的作用越明显;在沉降过程中,水平排列的双颗粒垂直下落速度大于单颗粒的沉降速度,且呈波动增长。研究结果可为钻井现场工艺实施、颗粒在黏性流体中的沉降机理及相关工程应用研究提供一定的参考。Aiming at the sedimentation of cuttings in the drilling fluid under the condition of drilling stopping during the drilling process,the spherical particles and polyacrylamide(PAM)solution were chosen to substitute for cuttings and drilling fluid,respectively.The computational fluid dynamics-discrete element method(CFD-DEM)was used to simulate the sedimentation process of single and double particles in PAM solution,and the effect of particle size and PAM solution concentration on the sedimentation process of the single particle as well as that of particle size and initial distance of particles on the sedimentation process of the double particles arranged horizontally were analyzed.The force on the particles was briefly analyzed.The results showed that the sedimentation velocity of the single particle in PAM solution was smaller than that in water,and it increased with the increase of particle size and decreased with the increase of PAM solution concentration;the Magnus and Saffman forces significantly effected the sedimentation of the double particles arranged horizontally,and the smaller the distance of double particles and the larger the particle size,the more significant the effect of Magnus force.Moreover,compared to single particles,the vertical descent speed of double particles arranged horizontally during the sedimentation process was greater than that of single particles and shows fluctuating growth.This study will provide certain reference for the research on process operation of the drilling site,the sedimentation mechanism of particles in viscous fluids and related engineering application.

关 键 词：双颗粒 颗粒间距 沉降速度 非牛顿流体 数值模拟 

分 类 号：O359[理学—流体力学]