液基全过程欠平衡钻井停止循环连续气侵井筒瞬态流动  

Transient flow in continuous gas invasion wellbore under condition of circulation cease in liquid-based whole process underbalance drilling

作　　者：魏纳[1] 孟英峰[1] 李皋[1] 李永杰[1] 万里平[1] 李红涛[1] 刘佳洁[1] 刘金龙[1] 

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500

出　　处：《中国石油大学学报（自然科学版）》2012年第6期74-78,共5页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家科技重大专项(2011ZX05021-003);国家“973”计划课题(2010CB226700);中央财政支持地方特色重点学科建设项目;国家自然科学基金项目(51104124,51204140)

摘　　要：液基全过程欠平衡钻井井筒流动过程主要包括正常钻进时稳态气液固多相流动以及停止循环条件下的瞬态气液两相流动。建立停止循环开井条件下遇到连续气侵时井下瞬态气液两相流动特征参数变化数值模拟计算方法及数学求解模型,计算对比遇到不同气侵量的井下气液两相流特征参数变化。结果表明:较大气量条件下气体运动速度更快、顶出钻井液更多、井底流压波动更大;井口回压的施加能有效控制井下气体膨胀与井底压力波动。The bore flow model of liquid-based process underbalance drilling includes the steady-state gas-liquid-solid multi- phase flow of normal drilling and transient gas-liquid two-phase flow under conditions of circulation cease. For circulation cease open wells, the numerical simulation methods of characteristics parameters change of downhole transient gas-liquid two-phase flow with continuous gas invasion and mathematics to solve the model were developed. The gas-liquid two-phase flow character- istic parameters were calculated in the different size of the gas influx of underground. The results show that the larger gas vol-ume leads to the faster movement velocity, the more knocking out drilling fluid and the larger bottom hole flowing pressure fluctuation. The exerting of wellhead back pressure can effectively control the underground gas expansion and the bottom hole pres-sure fluctuation.

关 键 词：钻井 全过程欠平衡 停止循环 气侵 瞬态流动 

分 类 号：TE21[石油与天然气工程—油气井工程]