摘要
通过室内土箱试验验证HYDRUS-2D模拟膜调控润灌水分运移的可行性,并探究通量一定时膜规格对湿润锋运移的影响规律。基于HYDRUS-2D,对膜处理40 cm×35 cm、40 cm×30 cm、40 cm×25 cm、40 cm×20 cm(下膜边长×上膜边长)在相同通量的情况下膜规格对膜调控润灌湿润锋运移的影响。结果表明:(1)在对室内试验与数值模拟试验的误差分析中,各个观测点含水率的相对误差都在10%以内,相对误差的平均值为4.28%,对于湿润锋实测值与模拟值的误差分析中,均方根误差变化范围为1.28~3.20 cm,3个方向全部湿润锋运移距离的模拟值与实测值的均方根误差为2.41 cm,证明了HYDRUS-2D对于膜调控润灌数值模拟的可行性;(2)灌水结束后,各个膜处理的上膜水量都要大于下膜水量,并且上膜最小时湿润锋垂直向上的运移距离最大,为29.04 cm,膜上水量也最大,百分比为79.57%,湿润锋垂直向下的运移距离最小,膜下水量也最小;上膜最大时湿润锋垂直向上的运移距离最小,为23.03 cm,膜上水量也最小,百分比为66.33%,湿润锋垂直向下的运移距离最大,膜下水量也最大;表明膜规格的改变能够很好地调控上下膜的水量,上膜的减小能够有效减少膜下渗漏的水量;(3)膜调控润灌湿润锋垂直向上与水平向右的运移距离与时间存在着明显的幂函数关系,垂直向下的湿润锋运移距离与时间存在着明显的线性关系。
Indoor soil box experiments were conducted to verify the feasibility of Hydrus-2D numerical simulation for membrane-regulated subsurface drip irrigation and reveal the influence of membrane specification on the wetting front transport at a certain flux.Based on Hydrus-2D,effects on wetting front transport under the same flux were compared in membrane treatments covering with membrane size of 40 cm×35 cm,40 cm×30 cm,40 cm×25 cm and 40 cm×20 cm(lateral length of superior membrane×side length of inferior membrane).The results showed that:(1)In the error analysis between the indoor experiment and numerical simulation,the relative error of moisture content of each observation point was within 10%and the relative error was 4.28%.The root mean square error range of the wetting front was 1.28-3.20 cm and the root mean square error of wetting front transport distance in all three directions between the simulated values and measured values was 2.41 cm.These results suggested that Hydrus-2D was feasibility for the numerical simulation in the membrane-controlled subsurface drip irrigation.(2)Water amount above the upper film was larger than that under the lower film in the four film treatments.When the upper film was the smallest,the vertical upward migration distance of the wet front was the largest(29.04 cm),and the upper film water amount accounted for 79.57%that was the largest percentage in the four membrane treatments.The vertical downward migration distance of the wet front was the smallest when the water amount under the film was also the smallest.And when the upper film reached its maximum,the vertical migration distance of wetting front was the smallest(23.03 cm),and the water amount on the film was also the smallest,(66.33%).But the vertical migration distance of wetting front was the largest,and the water amount under the film was also the largest.The results indicated that the change of membrane size could regulate the water content of the upper and lower membrane,and the decrease of the upper membrane coul
作者
段启蒙
绳莉丽
程伍群
张西平
韩明明
吴现兵
DUAN Qimeng;SHENG Lili;CHENG Wuqun;ZHANG Xiping;HAN Mingming;WU Xianbing(Agricultural University of Hebei Province Urban and Rural Construction Institute,Baoding 071000,China)
出处
《河北农业大学学报》
CAS
CSCD
北大核心
2022年第2期120-130,共11页
Journal of Hebei Agricultural University
基金
国家重点研发计划项目(2017YFD020170703)
河北省重点研发计划项目(19226425D)
河北省水利科研计划项目(2018-30).
关键词
膜调控润灌
HYDRUS-2D
膜规格
湿润锋
通量
相对误差
membrane-regulated subsurface drip irrigation
Hydrus-2D
membrane specification
wetting front
flux
relative error