基于最优穿深分析的射孔参数优化设计新方法

射孔完井作为主要的完井方式之一，对套管井沟通储层、解除近井带污染、释放产能尤为重要，射孔参数的合理设计是保障射孔作业效果的关键所在。现有射孔参数设计方法主要通过表皮计算开展射孔参数敏感性分析，依据曲线形态、分布密集程度及变化趋势进行参数设计。由于射孔表皮计算模型未有效考虑射孔孔道流动摩阻的影响，无法准确刻画射孔穿深和产能之间关系，依据表皮分析的参数敏感性结果无法确定最优射孔穿深。从流体力学角度出发，将射孔孔道等效为微观意义上的水平井，建立油藏与射孔孔眼流动耦合数学模型，充分考虑射孔孔道流动摩阻的影响，结合Dikken优化原则，研究建立了最优射孔穿深确定方法，形成基于最优穿深分析的射孔参数设计新方法。实例分析表明，该方法可为最优射孔穿深的设计提供理论依据。

New Optimization Design Method for Perforation Parameter Based on Optimal Perforation Depth Analysis

As one of the main completion methods, perforated completion is especially important for the connection between reservoirs in cased wells, removal of the near-wellbore pollution, and maximization of production capacity. As such, design of the perforation parameter is the key to the effect of perforation. Existing design methods for perforation parameter mainly perform sensitivity analysis of the perforation parameter through surface calculations, and undertake parameter design according to curve shape, distribution density, and changing trend. As the calculation model for perforated surface does not effectively consider the influence of the flow friction of perforation tunnels, it is impossible to describe the accepted understanding of the relationship between the perforation depth and the production capacity accurately. Thus, the optimal perforation depth cannot be determined based on the results of parameter sensitivity analysis of the surface. From the perspective of fluid mechanics, the perforation tunnel can be viewed as equivalent to the horizontal well at microscale, and a coupled mathematical model of the flow between the reservoir and the perforation is established, which fully considers the influence of the flow friction of the perforation tunnels. Based on the Dikken optimization principle, a determination method for the optimal perforation depth is established, yielding a new design method for the perforation parameter based on optimal perforation depth analysis.