恒压喷灌系统田间允许调压范围的研究

恒压喷灌系统田间允许调压范围是系统设计的重要参数，关系到田间灌水质量。针对恒压喷灌系统几种压力变化情况，通过试验得到了系统的压力变化规律及一些常用喷头的旋转周期、喷洒强度等随压力变化的一些基本资料，分析了压力变化对平均喷灌强度及组合均匀度的影响。结果表明，在一定压力变化范围内，系统压力的周期变化对平均喷灌强度及组合均匀度影响较小，但不同时段系统在不同压力工况下工作时，则对其影响较大。由此建立了田间喷灌强度及组合均匀度与压力变化的相互关系，给出了根据田间灌水质量要求所确定的压力变化幅度的计算式。

Research on Permit Range of Pressure Regulation in the Field Pipe of Constant Pressure Sprinkler Irrigation System

The permit range of pressure regulation in the field is an important parameter on designing constant pressure sprinkler irrigation system, and affects on the irrigation quality. By testing analysis of the conditions under a few pressure changing in the constant pressure sprinkler irrigation system,the rule of the pressure change and some common basic data, such as cycle of the sprinkler turning around, sprinkler intensity and the combined uniformity changing with the pressure were found out. The effects of the pressure changing on the average sprinkler intensity and the combined uniformity were analyzed. The cycle of pressure change has few effects on the average sprinkler irrigation intensity and the combined uniformity. But within the range of pressure changing in different time, the pressure will affect the system working significantly. According to these,the relationship of changes between the sprinkler intensity in the field and combined uniformity and the pressure were built.