An improved analytic solution is presented to estimate soil water infiltration by surface irrigation methods through a more rigorous determination of the subsurface shape factor, as applied in volume-balance models. Based on the results of this analysis and by averaging the shape factor of previously published equations, a new relationship is presented, with a maximum error of 0.036%. Also, the effect of these relationships on the empirical parameters for the Kostiakov–Lewis equation and the water infiltration depth were evaluated. Based on this evaluation, the relative error difference of the infiltration depth of the actual subsurface shape factor value and the new relationship was less than 0.01%. Given the high accuracy of the proposed methodology and the simplicity of its form, this relationship is recommended for use in practical work to predict surface irrigation hydraulic performance and irrigation application efficiency.

中文翻译：

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地表灌溉水力学的地下形状因子

提出了一种改进的分析解决方案，通过更严格地确定地下形状因子（如在体积平衡模型中应用）来估计地表灌溉方法的土壤水分入渗。基于该分析的结果，并通过对先前发表的方程的形状因子进行平均，提出了一种新的关系，最大误差为 0.036%。此外，还评估了这些关系对 Kostiakov-Lewis 方程的经验参数和水入渗深度的影响。以此评价为基础，入渗深度实际地下形态因子值与新关系式的相对误差差异小于0.01%。鉴于所提出的方法的高精度和其形式的简单性，