多分支水平气井产能预测方法及其应用

多分支水平井能控制更大的储量面积,大幅度地提高油气藏采收率。为此,提出了考虑储层各向异性、断层和实际钻井轨迹影响的多分支水平气井产能预测方法。利用该模型分析了气藏中多分支水平井井型参数(分支长度、分支角度、分支数目)对单井产能的影响。结论表明:分支井筒与主井筒间的干扰以及分支井筒之间的互相干扰是影响多分支水平气井产能的主要因素;在实际应用中应采取4分支以上的分支数目,分支角度应不小于30°,应根据气藏需求选用尽可能大的分支长度。

productivity prediction method for multi-branch horizontal gas wells and its application

A larger area of reserves can be managed and significant increase in the recovery ratio will be achieved by multi branch horizontal gas wells, which in fact have been used more and more widely in China. In view of this, a study of productivity prediction method is presented here considering the impact of the reservoir anisotropy, fault and real well track by the use of the analytical model. Based on this model, the impact is analyzed of the branch wellbore parameters, including the length, angle and number, on the productivity of multi branch horizontal gas wells. The results have shown that (1) the disturbance between the branch wellbores and the main wellbores, and the disturbance among the branch wellbores themselves are the dominant factors which affect the productivity of multi branch horizontal gas wells, and (2) if a multi branch horizontal gas well is deployed in a real gas reservoir, at least four branches should be selected, the branch angle should be no less than 30°, and the branch length should be as large as possible according to the gas reservoirs.