摘要
为揭示含沙率对浑水膜孔灌单孔自由入渗特性的影响,通过室内浑水膜孔灌单孔入渗试验,研究了西安粉壤土在不同浑水含沙率(0、3%、6%、9%、12%)时的入渗特性,分别建立了不同浑水含沙率的膜孔灌单孔自由入渗垂直湿润锋运移距离、单位膜孔面积累积入渗量与入渗时间和含沙率的模型,并引入了减渗率来表述浑水含沙率对膜孔灌单孔自由入渗的减渗效果。结果表明,湿润锋运移距离、单位膜孔面积累积入渗量及稳定入渗率均随着浑水含沙率的增大而减小;在相同的入渗时间内,随着含沙率的增大,入渗系数K逐渐减小,减渗率η逐渐增大;不同浑水含沙率膜孔灌单孔自由入渗的减渗率与入渗时间之间呈极显著的幂函数关系;入渗初期的减渗率变化最大,入渗200 min以后的减渗率基本趋于稳定。
In order to unravel the effect of sediment content on water infiltration from a single hole in muddy wa- ter film hole irrigation system, we took Xi＇ an silty loam as example and conduced laboratory experiments to mea- sure water infiltration from a single hole when the sediment content was 0, 3%, 6%, 9% and 12% respectively. Models were established to link change in the vertical moving distance of the wetting-front, the cumulative infil- tration volume per unit area to infiltration time and sediment content. The results showed that with an increase in muddy content, the moving distance of the wetting front and the cumulative infiltration volume of per unit area, as well as the steady infiltration rate all decreased. In the same infiltration time, the infiltration coefficient de- creased as the muddy content increased, but the decay ratio of the infiltration increased with the muddy content. There was a strong power-law relationship between the infiltration decay ratio and the infiltration time. The infil- tration decay ratio changed dramatically during the initial infiltration process, but could be deemed to have reached steady state 200 minutes after the infiltration.
出处
《灌溉排水学报》
CSCD
北大核心
2017年第12期62-67,共6页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(51479161
51279157)
公益性行业科研专项资助项目(201203003)
陕西省教育厅基金项目(16JK1539)
关键词
含沙率
浑水膜孔灌
自由入渗
稳定入渗率
减渗率
sandy rate
muddy water film hole irrigation
free infiltration
steady infiltration ratio
infiltration decay ratio
