试井参数自动拟合优选新算法

A NEW OPTIMAL ALGORITHM FOR WELL TEST PARAMETER AUTOMATIC MATCHING

针对无限大均质油藏如何实现试井资料的自动分析,以保证解释结果的唯一性,一直是人们在积极探索的目标。提出了一种确定油藏参数的全局性优化算法:根据正交试验法原理,在未知参数(渗透率、井储系数、表皮系数)的可能变化范围内,通过试算,快速寻找出最佳参数组合。算法不依赖初始参数值的选取,不需要讨论模型解的有关分析性质。实例计算结果表明了该方法的有效性,可进一步扩展到其他油藏(如:天然裂缝油藏、复合油藏等)的试井理论分析中去。所述方法可用于估计更多油藏未知参数,如有界油藏的边界距离、多层油藏层与层间的窜流系数等。

In terms of the infinite homogeneity reservoirs,the automatic analysis of well test data and unique results are the goal of well testing.This paper proposes an algorithms of total optimization based on the method of the orthogonal experiment to estimate directly wellbore and reservoir parameters in single layered,boundless reservoirs from the possible bound of the unknown parameters.The algorithm does not depend on the initial guess of unkown reservoir parameters,such as permeability,accumulation factors and skin factors,and there is no need of the discussion of different analytic properties for model's solution.The case given demonstrates the effectiveness of the algorithm.This paper focuses on the study of the well testing in an infinite homogeneous reservoir.It can be popularized to other well test analysis of reservoirs,such as natural fractured reservoirs and combined reservoirs.The method can be applied to estimate more unknown parameters of the reservoirs,such as boundary distance of the bounded reservoirs and crossflow factor of layered reservoirs.