模糊线性规划在微灌干管管网系统优化中的应用

Application of fuzzy linear programming to optimal design of micro-irrigation main pipe network

微灌干管管网各支管入口处压力具有模糊性,即该处压力在一定范围内变化不会影响工程正常运行。针对这一特点,本文分别建立了起点水压未给和已给的微灌干管管网系统优化设计的模糊线性规划数学模型,在模型的求解过程中,通过适当的变换,将模糊线性规划问题转化成一般线性规划问题,采用单纯形法求解。根据所建立的起点水压未给的微灌干管管网系统优化设计的模糊线性规划数学模型,可确定泵站扬程未定的机压微灌干管管网系统优化设计方案;根据所建立的起点水压已给的机压微灌干管管网系统优化设计的模糊线性规划数学模型,可确定泵站扬程已定的加压和自压微灌干管管网系统优化设计方案。与普通线性规划问题相比,这一方法可使设计结果更为经济合理。

The fuzzy linear programming mathematical model is established to optimize the microirrigation main pipe both for unknown and know water source pressure.In the calculation the model is transformed into an ordinary linear programming model and solved by means of simple form method.For microirrigation main pipe of undefined pump lift,the optimal design can be achieved based on fuzzy linear programming model for unknown water source pressure.Whereas,the optimal design of know pump lift or by gravity can also realize if the fuzzy linear programming model for know water source pressure is applied.