摘要
为研究微润灌土壤水分入渗特征和不同影响因素对其影响规律,基于微润管出流机理,采用HYDRUS-2D软件构建了微润灌土壤水分运动模型。利用室内试验实测数据验证了模型的准确性,参数敏感性分析表明模型模拟结果对微润管的形状和水力特征参数敏感度较低。不同情境模型模拟结果表明:微润灌下水分主要集中在管附近;土壤质地越黏重,微润灌湿润范围和湿润锋运移速率越小,湿润体水分分布等值线图越接近于同心圆;工作压力水头越高,湿润范围和湿润锋运移速率越大,且管附近土壤饱和度越高,但200 cm工作压力水头下土壤不易达到饱和;微润管埋深显著影响湿润体的位置和湿润锋到达上下边界的时间,但在湿润锋到达边界之前,其对微润管出流量和湿润锋运移速率影响不大。本研究可为微润灌系统设计管理优化和该技术的进一步推广应用提供参考。
This study aims at investigating the characteristics of soil water infiltration under moistube irrigation and the effect of different influencing factors on it.Based on the outflow mechanism of moistube,a mathematical model of water movement under moistube irrigation was established by using HYDRUS-2D.The validation was confirmed by the good agreement between the simulated and measured results.Sensitivity analysis shows that the simulated results are not sensitive to the shape and the hydraulic parameters of moistube.The simulated results of different situation show that the irrigation water is mainly concentrated near the tube.As the soil texture becomes heavier,the wetting area and the advancing velocity of wetting front decrease and the contour of moisture distribution is closer to“concentric circle”.With the increasing working pressure head,the wetting area,the advancing velocity of wetting front and the saturation degree of soil near the tube increase obviously.However,the soil can hardly become saturated under moistube irrigation under the working pressure head below 200 cm.The buried depth of moistube appreciably affects the position of wetting area and the time for the wetting front to reach the upper and the bottom boundary,but it has little effect on the outflow of moistube and the advancing velocity of wetting front.This study could bear recommendation for the optimization of moistube irrigation system and the further popularization of this technique.
作者
齐伟
张展羽
王策
黄明逸
刘畅
陈于
QI Wei;ZHANG Zhanyu;WANG Ce;HUANG Mingyi;LIU Chang;CHEN Yu(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;College of Agricultural Science and Engineering,Hohai University,Nanjing 211100,China;Rural Water Conservancy Science and Technology Development Center of Jiangsu Province,Nanjing 210029,China)
出处
《水利学报》
EI
CSCD
北大核心
2021年第9期1091-1102,共12页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(51879071,51579069)
中央高校基本科研业务费专项(B210203075)。
关键词
微润灌
出流机制
HYDRUS-2D
水分入渗
敏感性分析
影响因素
Moistube irrigation
outflow mechanism
HYDRUS-2D
water infiltration
sensitivity analysis
influencing factors
