煤层气水平分支井稳定性的数值分析  

Numerical analysis of coalbed methane horizontal branch well stability

作　　者：刘升贵[1] 彭智高[1] 李仲力 陈含[1] 

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083

出　　处：《辽宁工程技术大学学报（自然科学版）》2015年第7期769-773,共5页Journal of Liaoning Technical University (Natural Science)

基　　金：国家自然科学基金项目(41472130);中央高校基本科研业务费专项基金项目(2009QL09)

摘　　要：为研究煤层气水平分支井排采过程中井壁失稳的特征,利用COMSOL Multiphysics数值模拟软件,分析生产时水平分支井井筒周边储层中流体流动状态和岩体变形趋势,为煤层气生产井井壁稳定问题的评价和后续固井、完井工作提供依据.选取潞安矿区屯留羽状水平试验井抽采瓦斯项目LA-01H多分支水平井为研究对象,根据其井身结构,及测井、试井资料,建立一个大小为2 m×2 m×1 m的模型.研究结果表明:随着煤层气井排采的持续进行,井内流压不断减小,煤储层孔隙水压力降低,对井壁的支撑能力不足,井筒变形加大;分支连接段是水平分支井最薄弱的部位,应重点防护;必要时应对稳定性差的井段采取固井措施,并注意产时监控,防止失稳情况的产生.In order to study the stability characteristics of coalbed methane horizontal branch well in the process of drainage, this paper used COMSOL Multiphysics numerical simulation software to analysis the fluid flow state and rock mass deformation trend in the reservoir around wellbore during this period, prepared for the evaluation of borehole wall stability of production wells and provided the basis for subsequent cementing and completion work. The LA-01h multi-branch horizontal well of gas drainage project of Tunliu pinnate horizontal test well of Luan mining was selected as the study object. According to the wellbore structure, well log and well testing data, the model with size of 2 m ~ 2 m~ 1 m was established. The results show that, with the continuation of well drainage process, the flowing pressure of the wellbore continuous decreases, and so does the pore water pressure, which leading to the insufficient support ability of sidewall, then the wellbore deformation increases. The position of branch connection is the weakest parts of the horizontal branch wells and should be protected with high priority. When it is necessary, cementing measures should be taken for the poor stability position of wellbore, and close attention should be paid to production monitoring to prevent the formation of instability condition.

关 键 词：煤层气 数值模拟 水平井 井壁稳定 流体压力 

分 类 号：TP618.11[自动化与计算机技术—控制理论与控制工程]