水平井砾石充填参数优化设计的正交数值试验法

影响水平井砾石充填效果的施工参数包括砂浆排量、携砂比、携砂液黏度、冲筛比和滤失强度等,影响机理比较复杂,采用常规方法难以对其进行优化设计。首先确定这些因素的位级取值,然后使用正交表对其进行排列组合得到少量组合方案。利用水平井砾石充填数值模拟软件对这些组合方案分别进行数值试验,得到每种方案的充填效果评价指标;采用直观分析方法确定最优参数组合。对最优参数组合重新模拟表明,正交数值试验法得到的施工参数组合确实能达到最好的充填效果。采用方差分析法得到各因素对水平井砾石充填效果影响程度从大到小排序为:携砂比、冲筛比、充填排量、滤失强度、携砂液黏度。

Perpendicular Numerical Trial for Horizontal Well Gravel - Packing Optimization

The operation parameters for horizontal well gravel-packing concern slurry pump rate, gravel concentration, carrier fluid viscosity, wash-pipe diameter and filtration velocity. Because the mechanism of these parameters affecting the packing effect is very complicated, it's difficult to optimize them by normal method. In this paper, according to perpendicular form, the values for all levels of these parameters are permuted to make up of a few operation parameter combinations. The evaluation index of packing effect for every combination is calculated by the simulation program. Then, the optimum parameter combination is found out from all of results by direct analysis method, the re-simulation of which indicates that the packing effect of the optimum combination is really excellent. The variance analysis method is used to analyze the degree of all parameters influencing the packing effect, which are ranged from great to petty as followed: gravel concentration, wash-pipe diameter, pump rate, filtration velocity and fluid viscosity.