汪道兵;葛洪魁;周福建;熊春明;张景臣;严星明;

• 1:中国石油大学(北京)非常规天然气研究院

• 2:中国石油勘探开发研究院采油工程研究所

• 3:英国赫瑞.瓦特大学石油工程研究院

• 4:中国石油勘探开发研究院廊坊分院压裂酸化技术服务中心

摘要(Abstract)：

对油气井压裂改造时,向井眼内注入大量流体,井筒周围应力场重新分布,主要通过积分形式求解,过程繁杂,且对应力场的影响因素分析较少.利用拉氏变换,以流固耦合控制方程和应力平衡方程等为基础,结合注入流体诱导应力场的积分形式解,在定压条件下推导内、外边界拉氏变换解;利用Stephfest拉氏数值反演方法对变换解进行数值求解.数值模拟结果表明,切向应力场在最小水平主应力方向上变化较大,距离井壁越近,注入流体诱导的切向应力场值越大,随着距离增加,其值变小;在一定条件下(如地应力差较小),切向应力场发生反转,使得压裂裂缝转向.切向应力场与注入时间、流体黏度和地层渗透率等因素有关:延长注入时间、增加注入体积、较低的液体黏度和较高地层渗透率有利于使切向应力场增加,诱导切向应力场发生反转,有利于人工裂缝转向.

关键词(KeyWords)：拉氏变换;注入流体;诱导应力场;数学模型;切向应力;径向应力

Abstract:

Keywords:

基金项目(Foundation):国家重点基础研究发展计划项目(2015CB250903);; 国家自然科学基金重大项目(51490652);; 中国石油天然气股份有限公司科学研究与技术开发项目(2010E-2105)

作者(Author):汪道兵;葛洪魁;周福建;熊春明;张景臣;严星明;

Email:

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