| 摘要: |
| 根据油水两相渗流理论,考虑重力以及渗透率各向异性的影响，运用三维有限差分法模拟了大斜度井环境中 井筒周围压力、流体饱和度和电阻率的分布情况。模拟结果表明:斜井环境下，当井眼与原始储层存在明显压力差 时，重力对钻井液滤液侵人影响不明显;当储层渗透率为各向异性时,钻井液侵人不仅受储层水平渗透率影响，同时 受到储层垂向渗透率和井斜角度影响;淡水钻井液侵人造成井眼周围储层电阻率分布复杂，局部冲洗带电阻率可能 要高于原状地层电阻率,从而出现低阻环带特征。 |
| 关键词: 大斜度井 钻井液侵人 重力 饱和度 各向异性 电阻率 |
| DOI： |
| 分类号: |
| 基金项目:中石油中青年创新基金项目(06E1020);山东省自然科学基金项目(Y2007F25) |
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| Numerical simulation of drilling fluid invasion in highly deviated wells |
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YANG Zhen,LI Zhi-qiang,DENG Shao-gui, FAN Yi-ren, CHEN Hua
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(Faculty of Geo-Resource and Information in China University of Petroleum, Dongying 257061,Shandong Province, China )
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| Abstract: |
| Considering the influence of the gravity and the permeability anisotropy, the invasion pressure, fluid saturation and resistivity distribution in the highly deviated wells were numerically simulated with 3-D finite difference method on the basis of the filtration theory of oil-water two-phase flow. The simulation results show that the effect of gravity is generally slight if pressure difference between the borehole and the original formation is evident. Besides horizontal formation permeability ,the invasion is also affected by vertical .formation permeability and well deviation when formation permeability is anisotropic. The invasion of fresh drilling fluid resulted in the complex distribution of formation resistivity around the borehole. The resistivity of local flushed zone may be higher than the virgin zone resistivity and a low resistive zone appears in invading zone in the oil formation. |
| Key words: highly deviated well drilling fluid invasion gravity saturation anisotropy resistivity |
