摘要
水分运移是当今水文地质领域的研究热点,其在农业农田灌溉、水利水资源开发利用等方面有着较为广泛的应用。本试验基于图像法,通过在室内建立二维砂槽模型并装填粗砂粗砂透镜体,按照一定的时间间隔对水分运移过程进行拍摄,并在试验后整理和绘制锋面图,研究非均质砂土介质中水分的饱和过程中的分布规律和运移特征。研究表明中砂介质的入渗速度逐渐降低,粗砂透镜体的入渗速度逐渐增大,介质的非均质性会影响水分的运移,且介质的非均质性越大,水分运移波动越大,在粗砂透镜体和中砂介质的交界面附近水流会出现绕流,两者锋面线高差最大时约8~9 cm。水分运移还受到毛细力的作用,水分会向毛细管越多、孔隙越小的细颗粒方向优先运移,之后再填充粗砂透镜体。随着进行时间的增加,入渗速度降低。在粗砂透镜体和中砂介质的交界面非均质性较强,使得锋面线整体呈现“凹”型,但此阶段中砂介质的速度变化了0.044 cm/min,粗砂透镜体的速度变化了0.161 cm/min,在相同时间内,粗砂透镜体的入渗速度会快于中砂介质,说明粒径越大,渗透性越大,水分运移越快。
Water migration is a research hotspot in the field of hydrogeology.It is widely used in agricultural irrigation,water resources development.Therefore,the experiment based on image method,through the establishment of a two-dimen⁃sional sand tank model in the room and the loading of coarse sand coarse sand lens,according to a certain time interval to film the water migration process,and arrangement and drawing of the frontal map after the test toinvestigation the distribution law and migration characteristics of water in the process of saturation in heterogeneous sand media.Research shows that the infiltra⁃tion of Medium sand medium speed gradually reduce,coarse sand lens infiltration rate increase gradually.It shows that the mi⁃gration of water was affects by the medium heterogeneityand The greater the heterogeneity of the medium,the greater the fluctu⁃ation of water migration.Water flow will occur around the interface between the coarse sand lens and the Medium sand medium and the height difference between the two front lines is about 8~9 cm at the maximum.The water migration is also affected by the capillary force,and the water will migrate to the fine particles with more capillaries and smaller pores,and then fill the coarse sand lens.With the increase of time,the infiltration velocity decreases.In the interface of lenticular sand and Medium sand medium heterogeneity is stronger,present the"concave"type makes the front line,but in this stage,the speed of the sand medium has changed by 0.044 cm/min,and the speed of the coarse sand lens has changed by 0.161 cm/min.The infil⁃tration of coarse sand lens speed will be faster than the Medium sand medium,in the same time.It shows that the bigger the particle size,the greater the permeability,the faster the moisture migration.
作者
朱鹏锟
习伶宇
覃维维
薛森
苏椿惠
项广树
刘汉乐
ZHU Peng-kun;XI Ling-yu;QING Wei-wei;XUE Sen;SU Chun-hui;XIANG Guang-shu;LIU Han-le(Guangxi Scientific Experiment Center of Mining,Metallurgy and Environment,Guilin University of Technology,Guil-in,Guangxi 541004,China;Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology,Science and Education Integration Science and Technology Innovation Office,Guilin 541004,Guangxi)
出处
《地下水》
2021年第6期17-20,共4页
Ground water
基金
桂林理工大学大学生创新训练项目(202010596365、202010596010)。
关键词
图像法
二维砂槽
卵砾石粗砂透镜体
非均质多孔介质
水分运移
Image methods
Two-dimensional sand box
Coarse sand lens of gravel
porous media
Heterogeneous porous media
Water migration
