喷射角度及压力对微喷带喷洒水滴分布的影响  

Effects of spraying angle and pressure on the droplet distribution of micro-sprinkling hose

作　　者：王文娟 王文娥[1] 胡笑涛[1] 戴东科 Wang Wenjuan;Wang Wen’e;Hu Xiaotao;Dai Dongke(Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid 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水土工程教育部重点实验室,杨凌712100

出　　处：《农业工程学报》2021年第23期73-81,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金(52079113);陕西省自然科学基金(2020JM-166)。

摘　　要：微喷带灌溉具有节水省工、价格低廉、对动力要求低等优点。大田灌溉过程中,作物各生长期株高不同,各器官对水滴打击的耐受度不同,会对微喷带灌溉效果产生影响。为探究微喷带水量空间分布影响因素,该研究使用激光雨滴谱仪测量微喷带喷洒水滴的直径、个数和灌水强度,分析喷射角度(40°、60°及两孔组合)和工作压力(20、24、28和32 kPa)对水滴直径及分布的影响。结果表明:1)40°时的灌水强度峰值在17.9~23.0 mm/h,工作压力增大时灌水强度峰值波动不大。喷射角度为60°时,灌水强度峰值随着工作压力的增大逐渐降低。两孔组合灌溉时,微喷带的灌水强度与单孔相比略有增高,存在两个峰值。2)同一喷射角度下,水滴直径会随着工作压力的增大而减小;相同工作压力下,随着喷射角度的增大,微喷带喷洒水滴的直径分布范围略有减小。3)喷射角度和工作压力均会影响喷洒水滴在空间上的粒径分布,喷洒水滴直径分布范围为0~2.50 mm,占比较多的水滴直径集中在0.45~1.25 mm。该研究着重探究微喷带喷洒水滴的灌水强度和直径的空间分布,以期为微喷带的合理设计和推广应用提供基础理论支撑。A micro-sprinkling hose has been a promising type of equipment for water-saving irrigation,due to the cheap,easy to lay and pack up when working.The performance of the micro-sprinkling hose depends on the kinetic energy in the process of field irrigation.Correspondingly,the intensity of kinetic energy can be determined by the droplet distribution of spraying water in the air,where the irrigation water is sprayed from the thin pipe within regular orifices.There is also a different tolerance of various plant organs to the kinetic energy of droplets sprayed from the micro-sprinkling hose.Particularly,the plant height and the canopy coverage of crops vary greatly in each growth period.In this study,an indoor irrigation experiment was carried out to explore the influence of spraying angle and pressure on the droplet distribution of micro-sprinkling hose.An N44-5 micro-sprinkling hose was used,where“44”was defined as the folding diameter of 44 mm,and“5”was represented a group of five orifices on the pipe wall of the micro-sprinkling hoes.Four working pressures were set,including 20,24,28,and 32 kPa,expressed as P20,P24,P28,and P32.Three spraying angles were also set,including 40°,60°,and two-angle combinations,expressed as A40,A60,and A4060.A total of 12 working conditions was completed in the entire experiment.The measuring points were arranged in the wet area of the micro-sprinkling hose.Then,the irrigation water was sprayed from the single or two holes of the micro-sprinkling hose under different conditions,where the spraying water droplets were passed through the measuring area of the instrument.An LPM instrument was developed to measure the droplet number,diameter,velocity,and irrigation intensity of the spraying water.The results showed that:1)The irrigation intensity at A40 was relatively stable,with the production of working pressure,where the intensity was 17.9-23.0 mm/h.Meanwhile,the irrigation intensity decreased gradually,with the increase of the working pressure at A60.When the two angles were co

关 键 词：灌溉 压力 喷射角度 微喷带 灌水强度 水滴直径 

分 类 号：S275.5[农业科学—农业水土工程]