引黄滴灌不同含沙率对灌水器堵塞影响和试验研究

Experimental study on the clogging effect of drip irrigation emitters with different sediment concentrations

灌水器堵塞是影响黄河水滴灌灌水质量的关键因素。对8种不同灌水器与1‰(1 kg/t)、2‰(2 kg/t)、4‰(4 kg/t)3种含沙率进行模拟试验,重点研究了引黄滴灌不同类型滴灌灌水器的流量变化规律和堵塞效应。试验结果表明:灌水器的流量衰减率随着灌水历时的增加而增大,灌水300 h后衰减率整体达到43%~72%;流量衰减率随着含沙率的增加而增大,低泥沙含量时(1‰),75%的灌水器呈现中度堵塞情况,高泥沙含量时(4‰),100%的灌水器呈现重度堵塞。灌水器N-1.6与N-2.0B在3种不同含沙率下的灌水均匀度均达到80%以上,可以满足作物的灌溉需求。灌水器的流量衰减与灌水器的流道长度呈正相关,随着流道长度的增加,灌水器抗堵塞性能降低,流量衰减率增大。流道内沉积泥沙的中值粒径与灌水器设计流速呈负相关,随着设计流速的增加而减小。灌水器流道内0~30μm粒径的沉积泥沙体积比随含沙率的增加而不断降低。研究成果可为解决引黄滴灌灌水器堵塞问题提供参考。

The blockage of emitters is a key factor affecting the quality of water drip irrigation with the Yellow River water.This article focuses on the flow rate changes and clogging effects of different types of drip irrigation emitters in Yellow River water irrigation.The blockage simulation experiments were conducted on eight different drip irrigation emitters and three sediment concentrations of 1‰(1 kg/t),2‰(2 kg/t),and 4‰(4 kg/t).The results show that the flow attenuation rate increases with the increase of irrigation time,and the overall attenuation rate reaches 43%to 72%after 300 hours of irrigation.Furthermore,the flow attenuation rate also increases with the increase of sediment concentration,the emitters with low sediment content(1‰)of 75%exhibit moderate blockage;whereas those with high sediment content(4‰)of 100%exhibit severe blockage.The irrigation uniformity of emitter N-1.6 and N-2.0B under three different sediment concentrations are all above 80%,which can meet the irrigation needs of crops.The flow attenuation of the emitter is positively correlated with the length of the flow channel in the emitter.As the length of the channel increases,the anti-clogging performance of the emitter decreases,and the flow——attenuation increases.The sediment d 50 in the flow channel is negatively correlated with the design flow velocity of the emitter,which decreases with the increase of the design flow velocity.The sediment volume ratio of particle size of 0~30μm inside the flow channel decreases with the increase of the sediment concentration.The research results can provide reference for solving the problem of drip irrigation emitters clogging with the Yellow River water.