基于计算流体力学与离散单元法并行计算的煤层气井大粒径岩屑运动规律初探

发布时间：2018-01-05 12:04

本文关键词：基于计算流体力学与离散单元法并行计算的煤层气井大粒径岩屑运动规律初探　出处：《科学技术与工程》2017年15期 　论文类型：期刊论文

【摘要】：在计算流体力学与离散单元法(CFD-DEM)耦合并行计算的基础上,对大粒径、非球体岩屑在煤层气井"扩径"井段的沉积及运移规律进行了数值模拟。利用FLUENT建立了井眼交汇处"扩径"井段计算模型。利用DEM软件建立大粒径岩屑颗粒的离散元模型。借助集群并行计算优势,首先通过与实验数据的对比证实该CFD-DEM耦合模型的计算精确性、可用性;随后,基于钻井现场岩屑颗粒的采样及对其粒径、形状统计,将岩屑颗粒简化为片状进行计算。对不同粒径岩屑在"扩径"井段的运移及沉积过程进行了模拟再现,量化了粒径对岩屑在该区域的运移能力的影响。研究发现,在通过"扩径"区域时绝大部分的岩屑颗粒将沉积,体现了"扩径"段对大颗粒岩屑的"收纳"作用;岩屑粒径对运移能力有关键影响,粒径岩屑的增加造成其运移能力的指数形式衰减;而钻井液排量的增加对提升携岩能力效果不够明显。分析结果对地下钻井工程具有实际参考意义。
[Abstract]:On the basis of the parallel computation of computational fluid dynamics and discrete element method CFD-DEM, the large particle size is calculated. The deposition and migration of non-spherical cuttings in the "expanding diameter" section of coalbed gas wells are numerically simulated. The "expanding diameter" at the wellbore intersection is established by using FLUENT. The DEM software is used to establish the discrete element model of large diameter cuttings. The advantage of cluster parallel computing is obtained. Firstly, the accuracy and availability of the CFD-DEM coupling model are verified by comparing with the experimental data. Then, based on the sampling of cuttings on the drilling site, the size and shape of the cuttings are counted. The cuttings are simplified to flake shape and the migration and deposition process of cuttings with different sizes in the "extended diameter" section are simulated and reproduced. The effect of particle size on the migration ability of cuttings in the region is quantified. It is found that most of the debris particles will be deposited through the "expanding" area. It reflects the "absorption" effect of the "expanding diameter" section on the large granular cuttings. The grain size of cuttings has a key effect on the migration capacity, and the increase of the diameter of cuttings results in the exponential attenuation of the migration capacity of the cuttings. However, the increase of drilling fluid displacement is not enough to improve the rock carrying capacity, and the analysis results are of practical significance for underground drilling engineering.
【作者单位】：中国石油大学机电工程学院;海洋石油工程(青岛)有限公司;中国石油大学储运与建筑工程学院;
【基金】：国家自然科学基金(51274231、51374228)资助
【分类号】：TE24
【正文快照】： 中国石油大学储运与建筑工程学院3,青岛266580)(51274231、51374228)资助引用格式:邵兵,闫怡飞,毕朝峰,等.基于计算流体力学与离散单元法并行计算的煤层气井大粒径岩屑运动规律初探[J].科学技术与工程,2017,17(15):42—47Shao Bing,Yan Yifei,Bi Chaofeng,et al.Primary resea

【相似文献】