摘要
基于3维颗粒流数值模型,从细观角度模拟油藏恒速持续流动时的砂岩力学响应,分析出砂的发生和发展过程.射孔周围砂岩的应力变化曲线说明油藏流动增大砂岩的应力,持续时间越长,应力增幅越大,砂岩更易剪切屈服而破坏,出砂几率越大.油藏恒速持续流动时,砂岩的颗粒粘结剪应力比张拉应力的增幅更明显,说明砂岩的破坏以剪切为主.颗粒的平均位移和旋转再次说明油藏的持续流动增大了油井的出砂几率.结果表明油藏的持续高速流动对砂岩受力干扰较大,出砂几率增大,为持续开采中的出砂与产能平衡提供了重要的科学依据.
A numerical model based on particle flow code in 3 dimensions (PFC3D) was forwarded to simulate the continuous flowing affecting the mechanical characteristics of sand from the micro perspective, and the sanding initiation and development were analyzed in depth. The stress curve near the perforation hole indicated that oil flowing had increased the sand stress, and continuous flowing for a longer time would increased the stress much more. Therefore the sand yielded more easily due to the shear failure and to the fact that the probability of the sand production was also much more. Also, the continuous oil flowing made the tensile stress increase more rapidly than the shear stress on the parallel bonds, with the results indicating a shear failure in the perforation sandstone. In addition, the particle displacement and rotation also showed that continuous flowing increased the probability of the sand production. The above results demonstrated that a higher speed of continuous flowing would seriously disturb the load condition and mechanical response of the sandstone to much more sand production. The results can provide an important base for a balance of the sand production and the oil productivity in continuous oil extraction.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第6期741-746,共6页
Journal of Lanzhou University(Natural Sciences)
基金
国家自然科学基金项目(51109231)
重庆市自然科学基金项目(cstc2012jjA90005)
武汉大学水资源与水电工程科学国家重点实验室开放基金项目(2012B100)
中央高校基本科研业务费专项资金项目(106112013CDJZR200004)
关键词
储层砂岩
长期作用
3维颗粒流程序
力学特性
出砂机理
reservoir sandstone
long-time action
particle flow code in 3 dimensions
mechanical characteristic
mechanism of sand production
