水平井注采井网多目标优化方法

随着水平井技术的发展,现有的优化方法考虑的因素已不能满足需要,因而有必要建立一种新的适用于水平井注采井网的多目标优化方法。依据渗流理论,重新推导了水平井注采井网渗流方程;通过对井网开发产能规律的分析,推导了新的适用于水平井注采井网的累积产油量方程;运用经济现金流量和经济学原理,推导了水平井注采井网注水开发的经济净现值公式,改进了采收率与井网密度公式,使其能应用于水平井井网;将波动前缘运动理论用于约束井网范围。以累积产油量和经济净现值作为目标函数,以井网控制面积和压差范围等作为控制条件,构建了多目标优化模型并进行了求解。该方法在阿曼某油田进行了应用,并用数值模拟方法进行了验证。结果表明,其具有较好的适用性。与其他优化方法相比,多目标优化方法适用于水平井井网优化,理论性强,并且能同时优化工程和经济目标从而得到全局最优解,为油藏工程方案设计提供较好的理论支持。

Research on multi objective optimization method of horizontal injection production patterns

Rational well patterns are essential for success of horizontal wells development in the field.This paper is aimed to provide a new multi-objective optimization method on injection-production patterns.The flow model of horizontal injection-produc-tion patterns is re-established based on reservoir fluid theory,while a new cumulative production function for horizontal patterns is derived by analyzing the deliverability fluctuation;an economic net present value (NPV) function of petroleum development has been improved and applied in horizontal well patterns;the theory of wave frontal movement has been utilized to limit the pattern scope.From the synthesis of all the aspects mentioned above,multi-objective optimization model of horizontal injective-productive patterns is established with cumulative production and economic NPV as its target function,the control area and the pressure drawdown of patterns as its controlled conditions.The optimization method studied in this paper is finally applied in a certain field in 0-man,and the results obtained from the method are verified to be valid by the reservoir numerical simulator.Compared with others,this method could be applied in horizontal well patterns and overall optimums could be obtained from the simultaneous optimization of engineering and economy.This study could make a theoretical support for project designs in reservoir engineering.