基于特征线法的畦灌施肥地表水流溶质运移模型研究

Study on Model of Overland Water Flow and Solute Transport to Border Strip Fertigation Based on Characteristic Curve Method

为实现畦灌施肥技术参数的优化组合,建立合理的模型工具至关重要。基于零惯性量模型和一维对流弥散方程ADE作为畦灌施肥水流和溶质运移方程,分别利用有限差和特征线法进行求解,建立基于特征线法的畦灌施肥地表水流溶质运移模型。以隐式有限差解法为对照,对特征线法引入的数值误差状况进行评价。结果表明,相对于隐式有限差解法,采取特征线法求解ADE时引入的数值震荡和数值弥散有显著减少,基于特征线法的畦灌施肥地表水流溶质运移模型更合理。

In order to realize the optimized combination of technical factors of border strip fertigation, it is necessary to establish a reasonable model tool. Based on zero-inertia model as flow equation solved by finite difference method, and 1D ADE as solute transport equation solved by characteristic curve method, a overland flow and solute transport model was established based on characteristic curve method. With finite difference method as contrast method, the numerical errors introduced by characteristic curve method were evaluated. The results suggested that when compared with finite method, the numerical errors introduced by characteristic curve method is obviously smaller, and the model of overland flow and solute transport based on the numerical errors introduced by characteristic curve method should be more reasonable.