基于短历时Philip入渗公式的产流模型

Surface runoff formation model based on Philip equation

在分析积水入渗条件下短历时Philip入渗公式特点基础上,建立了基于短历时Philip积水入渗公式的降雨产流模型。模型显示地表积水时刻与雨强平方成反比。利用降雨强度为0.082 cm/min、坡度为15°情况下实测累计降雨产流量推求了模型参数吸渗率,并利用获得的S分别计算了雨强为0.214 cm/min、坡度为5°,雨强为0.133 cm/min、坡度为5°和雨强为0.133 cm/min、坡度为15°情况下累积径流量,相对于实测累积径流过程,计算相对误差都在10%内,可以满足精度要求,说明基于短历时Philip入渗公式建立的降雨产流模型可以用于描述坡面降雨产流过程。

Infiltration and Runoff formation during rainfall is one of the key processes of field water cycle, and it is important to analyze the effective utilizations of rainfall water and runoff formation. In the paper, the runoff formation mathematical model was developed based on the Philip equation describing ponding infiltra- tion processes. The parameter,S, is only included, and the model in math is simple. The model also shows that the ponding water time is the function of the square of the rainfall intensity. The experimental data for 0. 082 cm/min for rainfall intensity and 15° for slope was used to estimate the parameter, S, and the cumulative runoff amount for 0. 214 cm/min for rainfall intensity and 5° for slope, for rainfall intensity 0. 133 cm/min and 5° for slope,and for rainfall intensity and 15° for slope were calculated by the model based on the estimated parameter value. The relative error for calculated cumulative runoff amount compared to the meas- ured value is less than 10 %, and the results indicate that the model can be used to calculate the runoff.