Li Hao, Li Hong, Han Qibiao, Huang Xiuqiao, Jiang Yue, Sun Hao, Li Hui
Research Center of Fluid Machinery Engineering and Technology, Jiangsu University Zhenjiang 212013 China.
Institute of Farmland Irrigation, Chinese Academy of Agricultural Sciences Xinxiang 453002 China.
RSC Adv. 2020 Oct 23;10(64):38912-38922. doi: 10.1039/d0ra07782h. eCollection 2020 Oct 21.
Drip emitter clogging is closely related to the presence of particulate matter, nutrients, organic matter and microorganisms in irrigation water and severely restricts the performance, service life and popularization of drip irrigation systems. Micro/nanobubbles can effectively remove suspended particles in water, limit microbial activity, and significantly increase the concentration of dissolved oxygen in water to promote crop growth. However, the effects of micro/nanobubbles on drip emitter clogging remain to be studied. Thus, taking micro/nanoaerated drip irrigation as the research object, five different types of emitters were selected, and the clogging characteristics of the different types of emitters under micro/nanoaerated conditions were studied by performing an emitter clogging test. The influence of emitter clogging on the uniformity of the irrigation provided by the micro/nanoaerated drip system was explored. The results showed that emitter clogs developed gradually and that the clogging developed slowly at the early stage of irrigation. When a slight clogging occurred, the emitter clogged rapidly, resulting in severe or even complete clogging. The cylindrical emitters had the worst anti-clogging performance among the tested emitters, while the emitters with no pressure compensation function and high rated flows had the better performance. Micro/nanoaeration had a significant effect on emitter clogging and increased the normal working times of the E1, E2, E3, E4 and E5 emitters by 38%, 20%, 30%, 28% and 130%, respectively. In addition, micro/nanoaeration reduced the sensitivity of the Christiansen uniformity coefficient () and the statistical uniformity coefficient () in the drip system to the discharge ratio variation (Dra) and enhanced the stability of the uniformity coefficients of the drip system. Therefore, micro/nanoaeration can help to inhibit clog development in emitters, extend the service life of emitters, and maintain good uniformity in drip irrigation systems. The results of this paper provide a theoretical reference for revealing the clogging mechanisms of micro/nanoaerated drip irrigation emitters and provide theoretical support for the efficient operation of micro/nanoaerated drip irrigation systems.
滴头堵塞与灌溉水中颗粒物、养分、有机物和微生物的存在密切相关，严重限制了滴灌系统的性能、使用寿命和推广。微/纳米气泡可以有效去除水中的悬浮颗粒，限制微生物活性，并显著提高水中溶解氧的浓度以促进作物生长。然而，微/纳米气泡对滴头堵塞的影响仍有待研究。因此，以微/纳米曝气滴灌为研究对象，选择了五种不同类型的滴头，通过进行滴头堵塞试验研究了不同类型滴头在微/纳米曝气条件下的堵塞特性。探讨了滴头堵塞对微/纳米曝气滴灌系统灌溉均匀性的影响。结果表明，滴头堵塞是逐渐发展的，在灌溉初期堵塞发展缓慢。当出现轻微堵塞时，滴头迅速堵塞，导致严重甚至完全堵塞。在所测试的滴头中，圆柱形滴头的抗堵塞性能最差，而无压力补偿功能且额定流量高的滴头性能较好。微/纳米曝气对滴头堵塞有显著影响，使E1、E2、E3、E4和E5滴头的正常工作时间分别增加了38%、20%、30%、28%和130%。此外，微/纳米曝气降低了滴灌系统中克里斯琴森均匀系数（）和统计均匀系数（）对流量比变化（Dra）的敏感性，增强了滴灌系统均匀系数的稳定性。因此，微/纳米曝气有助于抑制滴头堵塞的发展，延长滴头的使用寿命，并在滴灌系统中保持良好的均匀性。本文的研究结果为揭示微/纳米曝气滴灌滴头的堵塞机理提供了理论参考，为微/纳米曝气滴灌系统的高效运行提供了理论支持。
