膜孔灌自由入渗土壤水分运动数值模拟

Numerical simulation of soil moisture movement in free infiltration type of film hole irrigation

以非饱和土壤水分运动理论为基础,建立膜孔灌自由入渗土壤水分运动的数学模型,利用室内试验对模拟结果进行分析验证,模拟值与实测值基本吻合,所建模型合理.用所建模型对不同因素组合下膜孔灌自由入渗土壤湿润体水分分布和入渗特性进行模拟分析,结果表明:土壤质地、容重、膜孔直径、初始含水率和灌溉水深对土壤水分分布模式影响很小.土壤质地、容重和膜孔直径对土壤累积入渗量和入渗速率影响较大,灌溉水深对土壤累积入渗量和入渗速率影响较小,初始含水率对土壤累积入渗量和入渗速率影响微弱.

Based on the unsaturated soil water movement theory,a mathematical model for the free infiltration type of film hole irrigation was developed.An indoor experiment was carried out to analyze and verify the simulation results and it was shown that the reasonable simulation values were principally consistent with the experimental values,showing that the model was the soil wetting moisture distribution and film hole infiltration characteristics of the free infiltration type of film hole irrigation were simulated and analyzed with this model for different factor combination.The result indicated that the soi1 texture,bulk density,film hole diameter,initial moisture and irrigation water depth would have a slighter influence on the soil moisture distribution pattern.The soi1 texture,bulk density and film hole diameter would have a greater influence on the water cumulative infiltration and Infiltration rate.The irrigation water depth would have a less influence on the water cumulative infiltration and infiltration rate.The initial moisture would have a slighter influence on the water cumulative infiltration and infiltration rate.