基于正交结果分析的内镶贴片式滴灌带性能优化设计

Optimization of Drip Irrigation Belt with Interior Embedded Patches Using Orthogonal Results Analysis

【目的】探究铺设坡度、含沙量、工作压力对内镶贴片式滴灌带的灌水均匀度和流量降幅的影响。【方法】开展了三因素三水平的均匀正交试验,采用极差分析和层次分析研究了铺设坡度、含沙量、工作压力对内镶贴片式滴灌带的灌水均匀度和流量降幅影响的主次顺序,运用PPR模型、NSGA-Ⅱ模型、线性回归模型进行对比分析。【结果】①各因素对灌水均匀度的影响排序为含沙量>铺设坡度>工作压力;对流量降幅的影响程度排序为含沙量>工作压力>铺设坡度;层次分析结果与极差分析结果一致,均表明含沙量对灌水均匀度和流量降幅的影响大。②基于试验数据构建灌水均匀度和流量降幅的线性回归模型,灌水均匀度线性回归模型的标准均方根误差为19.15%,流量降幅线性回归模型的标准均方根误差为14.81%,模型表现效果好。③构建灌水均匀度和流量降幅的投影寻踪回归模型,灌水均匀度投影寻踪回归模型的标准均方根误差为2.98%,流量降幅投影寻踪回归模型的标准均方根误差为2.42%,模型表现效果极好。【结论】PPR模型预测效果优于线性回归模型,且PPR模型与NSGA-Ⅱ预测结果较为一致,最优工况为:铺设坡度为0%,含沙量为1g/L,工作压力为96kPa,灌水均匀度为0.9585,流量降幅为0.0835。

【Objective】Embedding patches in drip irrigation belts is a technique to improve flow rate and irrigation uniformity.The purpose of this paper is to investigate the impact of various factors on performance of the embedded patches in improving irrigation uniformity.【Method】Using uniform orthogonal design of experiments with three levels of factors and experimental study,we analyzed the influence of sediment content,working pressure and slope on performance of the irrigation belt.The relationship between change in these factors and irrigation uniformity was analyzed using the PPR model,NSGA-II model and linear regression models.【Result】①The influence of the three factors on irrigation uniformity and flow rate reduction was ranked in the following order based on their significance:sediment content>land slope>working pressure.Analytic hierarchy process and range analysis both showed that sediment content had the greatest influence on irrigation uniformity and flow rate reduction.②Regression showed that irrigation uniformity and flow rate reduction were linearly correlated to flow rate,with the standard error for the former and the latter being 19.15%and 14.81%,respectively.③The projection tracking regression for change in irrigation uniformity and flow rate reduction showed that the standard error for the irrigation uniformity and flow rate reduction was 2.98%and 2.42%,respectively.【Conclusion】The PPR model was better than multiple regression model for predicting irrigation uniformity and flow rate reduction.Its results are consistent with that of NSGA-II.For the three factors we considered,the optimal working conditions for the drip irrigation belt with embedded patches were slope:0%,sediment content:1 g/L,working pressure:96 kPa,under which the irrigation uniformity was 0.9585 and the flow rate reduction was 0.0835.