边缝式迷宫滴灌带灌水器流道内泥沙沉积影响因素分析  

Influence of the emitter with tooth-shape labyrinth flow channel on sediment deposition

作　　者：王惠[1] 王世雷 王文娥[1] 胡笑涛[1] WANG Hui;WANG Shilei;WANG Wen’e;HU Xiaotao(Key Laboratory of Agricultural Soil and Water Engineering in Arid Areas,Ministry of Education,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学旱区农业工程教育部重点试验室,杨凌712100

出　　处：《农业工程学报》2023年第24期92-99,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(52079113,U2243235)。

摘　　要：为研究灌水器流道内泥沙颗粒淤积特性的影响因素,进一步降低物理堵塞发生的风险,该研究配置不同浓度(1.8、2.8、3.8 g/L)和不同粒径(0≤d<0.054 mm、0.054 mm≤d<0.075 mm、0.075 mm≤d<0.1 mm)的含沙水,进行全组合间歇滴灌堵塞试验,对含沙水灌溉下灌水器泥沙沉积特性进行分析并对灌水器内流态进行数值模拟研究。结果表明:灌溉结束后,经由边缝式迷宫灌水器输出的泥沙中,黏粒与砂粒比例下降,粉粒比例上升,即灌水器弯曲流道对小于0.002 mm和大于0.05 mm粒径的泥沙具有明显阻滞作用,流道内堵塞的泥沙集中在0.054~0.1 mm的中大粒径范围内。灌水器流道内部流线在主流区呈波浪状前进,主流区水流流速大于近壁区,中部转角处流速均偏大。沙粒易受上转角和下转角处产生的漩涡影响而沉降集中在漩涡中心及背水面。滞留在漩涡区内的泥沙颗粒是引起灌水器堵塞的主要因素。为减少灌水器堵塞风险,在设计优化时宜考虑减少直角、锐角区域以减少漩涡区的形成。研究为滴灌技术进一步推广和应用提供理论基础。Sediment deposition has posed a serious risk to the performance of emitter flow channels.This study aims to explore the influences of the emitter performance on sediment deposition,in order to reduce the risk of physical blockage occurrence.Different concentrations(1.8,2.8,and 3.8 g/L)and particle sizes(0≤d<0.054 mm,0.054 mm≤d<0.075 mm,0.075 mm≤d<0.1 mm)of sandy water were used in the emitter clogging test of intermittent drip irrigation.A comparison was also made on the particle size composition in the sediment output from the emitters that irrigated with the sandy water.A systematic analysis was then implemented for the sediment transport and siltation inside the emitters.A numerical simulation was also carried out to analyze the flow pattern in the emitter.The low-velocity or vortex zone was prone to clogging.An operation mode was finally recommended to improve the clogging-resistant performance of the emitters in the drip irrigation system,according to the flow pattern and the deposited sediments.The results show that:1)There was a consistent effect of side-seam labyrinth emitters on the size of settled sediment,with a decrease in the specific gravity of clay and sand particles,and the increasing specific gravity of powder particles.The grain size composition of the input original sediment was compared with the output one.There was a decreased proportion of clay and sand particles with an increased proportion of silt particles.Since the water-following property of sand particles was weaker than that of clay particles and silt particles,there was a weak discharge from the emitter with water.Specifically,the proportions of clay particles and sand particles in the sediment decreased by 1.14-2.98 percentage points and 1.55-11.14 percentage points,respectively,whereas,the proportion of silt particles increased by 1.25-13.74 percentage points.2)The low transport of large particle size was attributed to the small size of the labyrinth emitter flow channel.The clogging of the particle size was concentrated in t

关 键 词：灌溉 泥沙 数值模拟 滴灌系统 灌水器堵塞 迷宫流道 

分 类 号：S275.6[农业科学—农业水土工程]