考虑拖曳力的出砂预测新模型及应用

MODELING AND APPLICATION TO SAND PREDICTION CONSIDERING OF DRAG FORCE

雷征东 李相方 程时清

Lei Zhengdong Li Xiangfang Cheng Shiqing

中国石油大学, 北京 102249

China University of Petroleum, Beijing 102249

以往油井出砂预测模型都建立在静态基础上,与实际情况存在一定偏差。针对此问题,分析了射孔完成井的油层出砂机理,以线弹性理论为基础,以Fairhurst推导得到的井眼周围应力分布表达式为依据,得出射孔孔眼周围的应力表达式及射孔孔眼壁上任意位置的周向有效应力表达式,同时考虑变温应力和流体渗流作用的拖曳力影响,建立了一种新的射孔完井出砂预测模型。对实例井分析表明,该模型计算结果与实际情况更吻合。应用该模型研究了射孔方位、射孔参数对油井出砂的影响,结果表明深穿透射孔弹比大孔径射孔弹能更好地避免孔道出砂,采用定向射孔能有效地减少油井出砂问题。其结果对砂岩油藏射孔优化设计具有一定的指导意义。

After analyzing the mechanism of the sand entry of perforated well,based on the theory of linear elasticity and considering the effect of temperature-change stress and drag force of the fluid flow through porous medium,a new model for forecasting the sand production of perforated well is established.Through analyzing real well,it indicates that computational solution is more coincide with the reality.Using this model,the effect of perforation position and perforating parameter are researched.The result shows that deep penetrating BLTS is better than large size BLTS to avoid the sand production of pore passage,and oriented perforating is effective to diminish the sand production. There is some directive sense for.The conclusions are instructive in the perforation optimized design of sandstone reservoir.

10.3969/j.issn.1000-7393.2006.01.019