微地形影响下滴灌均匀度设计指标研究

首先对滴灌系统中田面微地形偏差、水力偏差、制造偏差三因素独立作用及共同作用下产生的滴头流量偏差率、偏差系数、均匀度的计算公式进行分析，对符合正态分布的田面局部高、滴头制造系数进行计算机模拟。并随机分配给滴头；然后借助计算机模拟计算出上述三种因素独立作用及共同作用下流量偏差率、偏差系数、均匀度等指标；最后将上述四种计算结果的500组数据。经过统计分析。确定了灌水均匀度计算公式，并建立了各均匀度参数之间的关系，分析得到的公式可直接用于滴灌系统的水力学计算。

Study on the Emission Uniformity for the Emitter under the Condition of Farmland Micro-terrain Action

The calculation formulas of the dripper flow variation rate, flow deviation coefficient and the emission uniformity for the emitter were analyzed in drip irrigation system. They are affected by farmland micro-terrain deviation, hydraulic deviation for the emitter and manufacture deviation for the emitter. The micro-terrain and manufacture coefficient, which accorded with the random of positive state distribution are imitated by computer program. The dripper flow variation rate, flow deviation coefficient and the emission uniformity for the emitter are calculated by using computer program under the four conditions. And the formula of the emission uniformity for the emitter and the relation of various uniformity parameters are proposed by statistic analysis of 500 groups data, which could be used to the hydraulic calculation of the drip system designs.