目前,广泛应用于边水气藏见水时间的计算模型主要是基于直井且忽略储层倾角推导而来,未综合考虑水平井水平段长度与储层倾角对计算模型的影响,随着气藏开发中水平井应用的不断增多,地层复杂性不断增大,现有模型的计算结果必然误差较大.针对这一问题,基于流体力学和气水两相渗流理论,在考虑水平段长度、储层倾角等因素的情况下,利用水平井渗流模型得到压力场分布,通过舌进速度反演见水时间,推导出倾斜地层条件下边水气藏水平井见水时间预测新模型,并进行了敏感性分析.现场实例计算分析表明,新模型的计算结果相对误差小于10%,相比于常用计算模型,精度提高了20% ~29%.敏感性分析表明,见水时间与水平段长度呈线性关系,水平段长度每增加10 m,见水时间增加230 d;见水时间与储层倾角基本属二次抛物线关系,储层倾角小于5°时影响并不显著,在储层倾角大于5°时见水时间增长迅速.研究成果对于边水气藏水平井的高效开发与合理配产具有一定的指导意义.%Current popular models for calculating water breakthrough time are established based on vertical wells without considering the influences of horizontal section length and dip angles on water coning. With the increasing of horizontal well and formation complexity in gas reservoir development, the current popular models cannot accu-rately predict the water breakthrough time of these wells. In order to solve the problem, based on fluid dynamics and seepage theory,a new mathematical model considering horizontal section length and dip angles was established based on the physical model and combining the pressure distribution and water-coning velocity formula. It is indi-cated from the case calculation analysis that the calculation error of this new model is less than 10%,which accura-cy is 20% ~29% higher than those of current popular models. And it is shown from sensitivity analysis that the wa-ter breakthrough time is in linear relation with horizontal section length. The water breakthrough time increases 230 d for every 10 m. Furthermore,the water breakthrough time is basically in quadratic parabola relationship with dip angle. When dip angle is less than 5°,the factor is not apparent. When dip angle is more than 5°,the break-through time increases rapidly. The research results can provide necessary technical supports for high-efficiency de-velopment of gas reservoirs with edge water.
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