动态水压间歇脉冲喷灌喷洒水力性能研究

Hydraulic Performance of Dynamic Water Pressure Intermittent Pulse Sprinkler Irrigation

动态水压喷洒和基于脉冲宽度调制的间歇喷洒对喷头喷洒水力特性均有显著调节作用,为充分发挥动态水压和间歇喷洒的技术优势,本研究通过压缩空气储能调节同步实现动态水压和间歇脉冲喷洒,基于此开发出新型动态水压间歇脉冲喷灌装置,并对动态水压间歇脉冲喷洒条件下的喷灌水力性能指标进行了实测和计算。结果表明,动态水压间歇脉冲喷洒模式下,喷头工作压力呈“急速上升—波动下降—急速下降”三阶段变化趋势,喷头流量较恒压连续喷洒降低70.23%~82.77%;径向喷灌强度呈双峰型分布,峰值喷灌强度为连续喷洒下的12.7%~33%;喷洒水量分布均匀度较连续喷洒有小幅降低5.8%~14.1%,且可通过运行参数优化进一步提升;水滴对表层土壤的打击强度显著降低,动能强度峰值降幅50.6%~70.9%。研究结果表明动态水压间歇脉冲喷洒可灵活实现喷洒水力性能指标的同步提升,具有较大应用潜力。

Both dynamic water pressure spraying and intermittent spraying based on pulse width modulation have significant regulating effects on the hydraulic characteristics of sprinkler spraying.In order to give full play to the technical advantages of dynamic water pressure and intermittent spraying,dynamic water pressure and intermittent pulse spraying synchronously were realized through compressed air energy storage regulation.Based on this,a dynamic water pressure intermittent pulse spraying device was developed.The hydraulic performance indexes of sprinkler irrigation under the condition of dynamic water pressure intermittent pulse spraying were measured and calculated.The results showed that under the dynamic water pressure intermittent pulse spraying mode,the working pressure of the sprinkler head presented a three stage change trend of“rapid rise—fluctuation decrease—rapid decline”,and the flow rate of the sprinkler head was decreased by 70.23%~82.77%compared with that of constant pressure continuous spraying.The radial irrigation intensity showed a bimodal distribution,and the peak intensity was about 12.7%~33%of that under continuous spraying.Compared with continuous spraying,the distribution uniformity of spraying water was slightly decreased(5.8%~14.1%),and can be further improved by optimizing the operating parameters.The impact intensity of water droplets on the surface soil was decreased significantly,and the peak kinetic energy intensity was decreased by 50.6%~70.9%.The results showed that the dynamic water pressure intermittent pulse spraying can flexibly improve the hydraulic performance index and had great application potential.