改进的水动力参数模型在非饱和土壤溶质运移问题中的应用  

Application of improved hydro dynamic parameters model for solute transport problem in unsaturation soil

作　　者：任长江[1,2] 王建华[1] 赵勇[1] 白丹[3] 龚家国[1] REN Chang-Jiang;WANG Jian-Hua;ZHAO Yong;BAI Dan;GONG Jia-Guo(China Institute of Water Resources ＆ Hydropower Research,Beijing 100038,China.E-mail： [e-mail];College of Water Conservancy ＆ Ecological Engineering of Nanchang Institute of Engineering,Nanchang 330099,China;Department of Water Resources ＆ Hydraulic Power,Xi＇an University of Technology,Xi＇an,710048,China)

机构地区：[1]中国水利水电科学研究院水资源所,北京10038 [2]南昌工程学院水利与生态工程学院,南昌3300993 [3]西安理工大学水利水电学院,西安710048

出　　处：《水动力学研究与进展（A辑）》2018年第4期480-489,共10页Chinese Journal of Hydrodynamics

基　　金：国家重点研发计划项目(2016YFC0401407;2016YFC0401400)~~

摘　　要：传统水分和溶质运移参数模型(导水率、扩散率和水动力弥散系数)只是含水率的函数,难以反映土壤初始含盐量以及溶液浓度对含水率和溶质入渗透性的影响。该文对传统以含水率为变量的水动力参数模型进行改进(引入反映浓度的参数α、β和γ),并通过室内不同初始含盐量(2、4、6、8和10g.kg-1)清水淋洗试验和不同浓度氯化钠溶液(0、15、25、50和100g.L-1)入渗试验对模型进行验证。试验表明土壤初始含盐量和入渗溶液浓度越大,相同入渗时间湿润锋和累积入渗量越小。数值模拟表明:(1)含水率和溶质浓度的实测值与计算值吻合较好,改进后的模型较传统模型精度提高了6.31%;(2)参数α、β和γ越大,相同位置含水率和溶质浓度越大,相同时间湿润锋运移距离越大。参数敏感性分析表明,参数α、β和γ对扩散率、导水率及水动力弥散系数的敏感度不受含水率的影响,但随着浓度的增大而增大。Because of the traditional model of unsaturated soil solute transport parameters（hydraulic conductivity,diffusivity,and the hydrodynamic dispersion coefficient） is only the function of water content,So it is difficult to reflect the influence of the solute initial salt content and solution concentration on the distribution of water content and solute.In this paper,the author improve the soil solute transport parameters model based on it,and provide a new model（the parameters denoted as（α,β,γ） which reflect the influence of the soil initial salt content and solution concentration on the distribution of water content and solute.Two groups of experimental has been carried out to verify the accuracy of improved model,one is the leaching experiment under the condition of initial soil salt content different initial（2、4、6、8、10 g.kg-1）,anther is the infiltration experiment under the condition of different solution concentration（0、15、25、50、100 g.L-1）.The experiment demonstrates that the higher of initial soil salt content and solution concentration the smaller the soil water content at the same distance,and the shorter distance of wetting front and cumulative infiltration at the same time.Numerical simulation shows that：（1） the measured values agree with calculated values for water content and solute concentration,the simulation accuracy is improved 6.31% than traditional model.（2） The better of the parameter α,β and γ the higher of water content in the same position,and the farther wetting front at the same time.Sensitivity analysis of model parameters shows that soil water content has no impact on sensitivity for parameter α,β and γ,but it increases as solute concentration.

关 键 词：溶质运移 蚁群优化算法 敏感性分析 

分 类 号：S278[农业科学—农业水土工程]