多裂缝水平井产能影响因素定量化分析模拟实验研究

Simulation experiment research on quantitative analysis of affecting factor on multi-fractures horizontal well productivity

运用水电相似理论和自主研发的水平井产能模拟实验装置,开展了多裂缝水平井产能影响因素定量化分析物理模拟实验研究,同时结合正交实验与灰色关联分析方法给出了裂缝参数对压裂水平井产能影响的重要程度排序及对水平井产能的贡献度。研究表明:裂缝长度增加水平井产能增大但产能增幅逐渐减小,当裂缝长度等于0.5倍水平井长度时,水平井产能增幅达到最大;裂缝条数增加水平井产量增大但产能增幅减小,裂缝条数大于3条时,水平井产能增幅明显变缓,增幅由22%降为4.3%;裂缝与井筒夹角变大水平井产能增大但对产能影响较小,仅提高产能0.9%~2.2%;多条裂缝存在时可以通过增大内部裂缝间距以及将裂缝交错分布的方式提高水平井产能5%~15%。裂缝参数对产能的重要程度排序及对产能的贡献程度为:裂缝条数(产能贡献度48.8%左右)、裂缝长度(产能贡献度26.5%左右)、裂缝间距(产能贡献度22.6%左右)、裂缝与水平井井筒夹角(产能贡献度2.1%左右)。该研究实现了多裂缝水平井产能影响因素重要程度排序及定量化分析,一定程度丰富了多裂缝水平井产能模拟理论。

Through the similar principle and the self-developed horizontal well productivity simulation experiment device,the simulation experiment research in multi-fractures horizontal well productivity affecting factor quantitative analysis was carried out. Then based on the orthogonal experimental design and the grey relational analysis,the importance and the contribution degree of the fracture parameter on well performance was analyzed. The results showed that,as the length of fractures increases,the production increases,the increasing range decreases,and the increasing range is maximal when length of fractures is half of the horizontal well. As the number of fractures increases,the production increases,and the increasing range is obviously decreased when the number is more than 3,the increasing range decreases from 22% to 4. 3%. As the angle between the fracture and the horizontal wellbore increases,the production increases,but the effect is weak,only 0. 9% ~ 2. 2%. Through changing fracture spacing and fracture distribution,horizontal productivity is increased about 5% ~ 15%. The productivity of a horizontal well is affected by the following fracturing parameters in a descending order：number of fractures（ productivity contribution degree is about 48. 8%）,fracture length（ productivity contribution degree is about26. 5%）,fracture spacing（ productivity contribution degree is about 22. 6%）,and the angle between the fracture and the horizontal wellbore（ productivity contribution degree is about 2. 1%）. This research has given multi-fractures horizontal well productivity affecting factor sort and quantitative analysis,enrich the theory of multi-fractures horizontal well productivity simulation to some extent.