不同冲洗措施下迷宫流道灌水器泥沙运行分布机理研究

Sediment Distribution Mechanism of Labyrinth-channel Emitters under Different Flushing Measures

摘要:

评估了3种冲洗流速（0.25、0.50、0.75m/s）和5种冲洗频率（2d冲洗1次、4d冲洗1次、7d冲洗1次、10d冲洗1次和无冲洗对照组）对内嵌式齿形迷宫流道灌水器抗堵塞性能的影响，利用激光粒度仪对水源泥沙、滴头排出泥沙、滴头内滞留泥沙进行级配对比和粒径分析，并对不同冲洗处理下灌水器的相对流量和灌水均匀度进行拟合。结果表明：冲洗处理对齿形迷宫流道灌水器抗堵塞性能有显著影响，12种冲洗处理提高了内嵌式齿形迷宫流道灌水器的输沙能力，使滴头使用年限平均提高了39.58%；在冲洗作用下，泥沙凝聚沉降的机会降低，流道内小颗粒泥沙及时排出，没有形成体积较大的团聚体，滴头堵塞形成缓慢，灌水均匀度和流量系数下降缓慢；冲洗处理能有效减少毛管内泥沙堆积，降低大颗粒泥沙进入迷宫流道的机率，从而提高了齿形迷宫流道灌水器的抗堵塞性能。

关键词:迷宫流道灌水器;堵塞;冲洗流速;冲洗频率;粒径分布

Abstract:

Flushing is the necessary measures of micro-irrigation system maintenance, the laboratory experiment was conducted at Kunming University of Science and Technology to evaluate the effect of three targeted flushing velocities (0.25m/s, 0.50m/s and 0.75m/s) and five flushing frequencies (flushing every two days, flushing every four days, flushing every seven days, flushing every ten days, and non-flushing control group) on the anti-clogging performance of the emitter. The laser particle size analyzer was used to analyze the particle size of the water source sediment, the sediment discharged by the dripper, and the retained sediment in the dripper. The relative flow rate and irrigation uniformity of the emitter were fitted under different flushing treatments. The results showed that the irrigation treatment had a significant effect on the anti-clog performance of the emitter, and the 12 irrigation treatment measures increased the service life of the emitter by 39.58% on average. Flushing can effectively reduce the accumulation of sediments in the dripline and decrease the probability of coarse particles flowing into emitters and fine particles aggregating and cementing in the labyrinth channel, thus relieving the emitter clogging. The capillary flush treatment improved the uniformity of irrigation and reduced the probability of sudden blockage of the emitter. Flushing can effectively reduce sediment accumulation in the capillary, reduce the probability of large sediment entering the labyrinth channel, and improve the anti-clogging performance of the drip head. Therefore, dripline flushing can effectively slow down clogging in muddy water drip irrigation system. The recommended flushing velocity should be set at 0.75m/s, and the flushing intervals should be extended appropriately but not more than 7 days.

Key words:labyrinth-channel emitters;plugging;flushing velocity;flushing frequency;particle size distribution