Many soils and other porous media exhibit dual- or multi-porosity type features. In a previous study (Seki et al., 2022) we presented multimodal water retention and closed-form hydraulic conductivity equations for such media. The objective of this study is to show that the proposed equations are practically useful. Specifically, dual-BC (Brooks and Corey)-CH (common head) (DBC), dual-VG (van Genuchten)-CH (DVC), and KO (Kosugi)1BC2-CH (KBC) models were evaluated for a broad range of soil types. The three models showed good agreement with measured water retention and hydraulic conductivity data over a wide range of pressure heads. Results were obtained by first optimizing water retention parameters and then optimizing the saturated hydraulic conductivity (K s ) and two parameters (p, q) or (p, r) in the general hydraulic conductivity equation. Although conventionally the tortuosity factor p is optimized and (q, r) fixed, sensitivity analyses showed that optimization of two parameters (p + r, qr) is required for the multimodal models. For 20 soils from the UNSODA database, the average R 2 for log (hydraulic conductivity) was highest (0.985) for the KBC model with r = 1 and optimization of (K s , p, q). This result was almost equivalent (0.973) to the DVC model with q = 1 and optimization of (K s , p, r); both were higher than R 2 for the widely used Peters model (0.956) when optimizing (K s , p, a, ω). The proposed equations are useful for practical applications while mathematically being simple and consistent.

中文翻译：

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多模态非饱和土水力特性通用模型的评价

许多土壤和其他多孔介质表现出双孔或多孔类型的特征。在之前的一项研究中（Seki 等人，2022 年），我们提出了此类介质的多峰保水性和封闭式导水率方程。本研究的目的是表明所提出的方程实际上是有用的。具体来说，双 BC（Brooks 和 Corey）-CH（普通头）(DBC)、双 VG (van Genuchten)-CH (DVC) 和 KO (Kosugi)1个公元前2个-CH (KBC) 模型针对广泛的土壤类型进行了评估。这三种模型在很宽的压头范围内与测得的保水性和水力传导率数据显示出良好的一致性。先优化保水参数，再优化饱和导水率（钾 秒 ) 和两个参数 (p,q） 或者 （p,r) 在一般导水率方程中。虽然通常曲折因素p被优化并且（q,r) 固定，敏感性分析表明优化两个参数 (p+r,qr) 是多模态模型所必需的。对于 UNSODA 数据库中的 20 种土壤，平均R 2个KBC 模型的 log（导水率）最高 (0.985)r= 1 和优化 (钾 秒 ,p,q). 这个结果几乎等同于 (0.973) 的 DVC 模型q= 1 和优化 (钾 秒 ,p,r); 均高于R 2个对于优化时广泛使用的彼得斯模型 (0.956) (钾 秒 ,p,A, ω). 所提出的方程对实际应用很有用，同时在数学上是简单和一致的。