正交试验设计在管道扩建优化设计中的应用

Application of orthogonal design in an optimal pipeline extension project

为了获得长输天然气管道干线扩建设计的最优方案,早日实现管网系统赢利的目标,以管道总年值费为目标函数建立了天然气管道系统参数优化设计模型,运用正交试验设计方法对模型进行求解,分别给出了水力约束条件、稳定性约束条件、管道强度约束条件和边界约束条件,并提出了采用正交试验设计法进行管道扩建优化设计的9个基本步骤。通过正交试验设计,不仅获得了各扩建管道与已建管道年值费用最低的最佳方案,还得到了管道管径、压力、压力比和管道壁厚等工艺参数的最优组合,实现了整个管网系统的全局优化设计。实例应用结果表明,该设计结果符合工程实际,该设计方法具有编程计算简单、计算次数少和不易漏掉最优方案的优点。

In order to really obtain the optimal program for the trunk line extension and to early achieve the goal of economic gains,the optimal design model of parameters of natural gas pipeline is established in which the annual cost is taken as the objective function. Firstly, solutions will be obtained by the orthogonal design while the hydraulic constraints, stability constraints, pipeline strength constraints, and boundary constraints are given respectively. Then, 9 basic steps of the orthogonal-based optimal design of pipeline extension are presented herein. Finally, with this optimal design method, not only the best program with the lowest annual cost for the pipes under construction or in the plan, but the optimal combination of pipeline diameter, pressure, pressure ratio and pipe wall thickness, etc., can be obtained, thereby the global optimization design of a pipeline network system will be achieved. Case studies show that this optimal design complies with the engineering practices and this optimal design method is characterized by simple and easy programming, few calculation times, and full consideration, providing reference for similar engineering projects.