多因素影响下膜孔灌单向交汇入渗特性

Unidirectional intersection infiltration characteristics of film holeirrigation under influence of multiple factors

为研究膜孔直径、膜孔间距、土壤初始体积含水率、入渗水头4个因素对膜孔灌单向交汇入渗特性的影响,通过室内土箱入渗试验资料来验证HYDRUS-3D模拟膜孔灌单向交汇入渗过程的可靠性,用HYDRUS-3D模拟不同膜孔直径、膜孔间距、土壤初始体积含水率、入渗水头条件下的单向交汇入渗过程,分析各因素耦合条件下单向交汇入渗规律,分别建立了各影响因素与单位膜孔面积累积入渗量、交汇时间、交汇面面积之间的经验模型.结果表明:4个因素对单位膜孔面积累积入渗量的影响程度从大到小依次为膜孔直径、土壤初始体积含水率、膜孔间距、入渗水头;对膜孔交汇入渗交汇发生时间的影响程度从大到小依次为膜孔间距、膜孔直径、土壤初始体积含水率、入渗水头;对入渗结束时交汇面湿润体面积的影响程度从大到小依次为膜孔直径、膜孔间距、土壤初始体积含水率、入渗水头.该研究结果可为确定最优膜孔灌技术要素组合提供理论依据.

In order to study the effects of 4 factors(namely film hole diameter,film hole spacing,initial volume water content of soil and infiltration water head)on the unidirectional intersection infiltration characteristics of film hole irrigation,the reliability of HYDRUS-3D simulated unidirectional intersection infiltration process of film hole irrigation was verified by the infiltration test data of indoor soil box.The unidirectional intersection infiltration process under different pore diameters,pore spacings,initial volume water contents of soil,and infiltration water heads were simulated by HYDRUS-3D.The unidirectional intersection infiltration rules under the coupling conditions of various factors were analyzed,and the empirical models between each influencing factor and cumulative infiltration per unit pore area,intersection time,and intersection surface area were established.The results show that the influence degree of the 4 factors on cumulative infiltration per unit pore area from large to small is pore diameter,initial volume water content of soil,pore spacing,and infiltration water head.The degree of influence from large to small on the occurrence time of film pore intersection is as follows:film pore spacing,film pore diameter,initial volume water content of soil,and infiltration water head.At the end of infiltration,the degree of influence on the wet-body area at the intersection surface is as follows:pore diameter,pore spacing,initial volume water content of soil,and infiltration water head.The research results can provide a theoretical basis for determining the optimal combination of film hole irrigation technology elements.