计数式全通径压裂滑套优化设计

为了提高内滑套步进压力，同时使得内滑套结构强度较高，提出一种优化计数式全通径压裂滑套的方法。采用最陡爬坡实验设计确定最佳响应区域；利用响应曲面法分别建立显著因子与步进压力及运动过程中内滑套所受最大应力之间的二阶响应模型并分析了各因子对各响应的影响；根据线性加权法确定目标函数，采用粒子群优化（PSO）算法寻优，得到内滑套最优结构参数；基于显式动力学方法模拟压裂球推动内滑套运动过程。结果表明，优化后，运动过程中内滑套所受的最大应力增大了9.2%，内滑套步进压力提高了40%。室内模拟实验表明，优化后，内滑套步进压力提高了44%，与数值模拟结果近似，最陡爬坡实验设计、响应曲面法以及PSO算法相结合用于内滑套结构参数的优化是有效的。

Optimization design of counter-type full-bore fracturing sliding-sleeve

To improve the stepping pressure and structural strength of inner sliding sleeve, an optimization method was proposed for counter-type full-bore fracturing sliding-sleeve in this study. The steepest ascent experiment was designed to determine the optimum response region. The response surface method was adopted to build the second-order response models between significant factors and stepping pressure as well as the maximum stress of inner sliding sleeve during the movement, respectively, so as to analyze the influence of each factor on the responses. The objective function was determined using the linear weighting method, and the particle swarm optimization (PSO)algorithm was employed to search and obtain the optimum structural parameters of inner sliding sleeve. Based on the explicit dynamic method, the process of the ball driving inner sliding sleeve was stimulated. The results show that after optimization, the maximum stress of inner sliding sleeve during the movement is improved by 9.2%, while its stepping pressure is increased by 40%. The laboratory experiments indicate that after the optimization, the stepping pressure of inner sliding sleeve is increased by 44%, similar to the numerical stimulation result. It can be summarized that the combination of particle swarm optimization algorithm, steepest ascent design and response surface method is an effective method for optimizing the structural parameters of inner sliding sleeve.