点源地下滴灌土壤水分运动数值模拟及验证

Numerical simulation and validation of soil water movement undersubsurface drip irrigation with point-source emitter

依据非饱和土壤水动力学理论,借助计算机数值模拟方法,应用Hydrus软件建立了地下点源滴灌的土壤水分轴对称二维数值模拟模型,分析对比了几种土壤条件下地埋点源滴灌时土壤水分的运动状况。应用土壤剖面含水率、土壤水湿润峰运移值和累积入渗量及入渗速率等指标的实测值与模型值对模型进行了验证。结果表明,两者具有较好的一致性,相对误差在10%以内,说明所建模型能比较真实地反映供试土壤条件下的水分运动情况。

Based on the theory of soil water dynamics and by means of computer simulation, a two-dimensional axial-symmetrical model was developed by using Hydrus-2D software. Some soil water movement conditions under subsurface drip irrigation with point-source emitter were calculated and compared. Results of simulation were verified by the measurement of soil moisture content, water front, cumulative infiltration and infiltration rate in laboratory test. The results showed that the simulation results agreed well with measurement values. The relative error between simulated and measured values is less 10% and so the predictability of the model is acceptable.