考虑裂缝井表皮因子非均匀分布的压力数值试井分析  

NUMERICAL WELL TESTING ANALYSIS OF PRESSURE CONSIDERINGNON-UNIFORM DISTRIBUTION OF SKIN FACTORS INFRACTURED WELLS

作　　者：杨胜芝[1] 付春波 杨龙[3] 赵娟 李尧 锁玉霞 YANG Shengzhi;FU Chunbo;YANG Long;ZHAO Juan;LI Yao;SUO Yuxia(The Eighth Oil Production Plant of Changqing Oilfield Company,Petro China,Xi’an 710021,China;The Second Oil Production Plant of Changqing Oilfield Company,Petro China,Qingyang 745000,Gansu,China;School of Petroleum Engineering,Yangtze University,Wuhan 430100,China;Xi’an Huaxian Petroleum Technology Company Limited,Xi’an 710065,China)

机构地区：[1]中国石油长庆油田分公司第八采油厂,西安710021 [2]中国石油长庆油田分公司第二采油厂,甘肃庆阳745000 [3]长江大学石油工程学院,武汉430100 [4]西安华线石油科技有限公司,西安710065

出　　处：《力学与实践》2023年第5期1128-1136,共9页Mechanics in Engineering

基　　金：陕西省科学技术厅油气田开发方案优化设计云平台项目(2019ZDLGY11-04)资助。

摘　　要：在对非常规储层的压裂井进行压力试井分析时,裂缝表皮因子通常考虑为单一定值,而由于压裂措施的复杂性,其裂缝周围区域的污染程度并非均匀单一,进而导致地层压力分布规律十分复杂。因此,为了准确地描述裂缝非均匀分布的污染区域,从裂缝表皮因子定义的角度出发,确定了非均匀分布的裂缝表皮因子公式,建立了对应的数值模型进行求解计算,并考虑不同表皮分布规律研究了压力试井曲线及压力场的变化规律。研究结果表明:裂缝表皮因子中心大两边小分布规律下,压力试井曲线过渡段凸起高度更高,线性流段持续时间变短,压降主要集中于裂缝根部位置;裂缝中心小两边大分布规律下,压力试井曲线过渡段凸起高度更低,径向流出现时间早,压降主要集中于裂缝中心位置。通过现场实例对比计算,进一步验证了模型的实用性,可为裂缝井的裂缝污染评价及压力分布评价提供一种新的应用方法,对非常规油气井的产能评价与认识有重要意义。When conducting pressure test analysis on fractured wells in unconventional reservoirs,the fractureskin factor is usually considered as a single fixed value.However,due to the complexity of fracturing measures,the pollution level in the surrounding area of the fractures is not uniform,resulting in a very complexdistribution pattern of formation pressure.Therefore,in order to accurately describe the pollution area of non-uniform distribution of fractures,from the perspective of the definition of fracture skin factor,the formula fordetermining the non-uniform distribution of crack skin factor was determined,and a corresponding numerical model was established the calculation.Different skin distribution patterns were considered to study the changesin pressure testing curves and pressure fields.The research results indicate that under the distribution pattern ofthe large center and small sides of the crack skin factor,the protrusion height of the transition section of thepressure testing curve is higher,the duration of the linear flow section is shorter,and the pressure drop is mainlyconcentrated at the root of the crack.Under the distribution pattern of small center and large sides of the crack,the protrusion height of the transition section of the pressure testing curve is lower,the radial flow occursearlier,and the pressure drop is mainly concentrated at the center of the crack.By comparing and calculating on-site examples,the practicality of the model was further verified,providing a new application method for theevaluation of fracture pollution and pressure distribution in fractured wells.The obtained results are useful forthe evaluation and understanding of unconventional oil and gas wells'production capacity.

关 键 词：裂缝井 压力分布 数值试井 表皮因子 产量模型 

分 类 号：TE353[石油与天然气工程—油气田开发工程]