Improvement and application of numerical models for non-Darcy flow based on Lagrangian method -for the purpose of on-site application-

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K15346
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Rural environmental engineering/Planning
• Research Institution: Ehime University
• Principal Investigator: Izumi Tomoki 愛媛大学, 農学研究科, 准教授 (40574372)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 非ダルシー流 / 地下水浸透流解析 / 粒子法

Outline of Final Research Achievements

In this study, a numerical model for the non-Darcy flow which is developed in the preceding research project is improved to obtain the versatility of the model and its applicability to two in-situ problems that are the rainfall infiltration flow on mountain slopes during heavy rainfall and the infiltration/drainage flow around the underdrain constructed under the multipurpose paddy fields is validated in order to address in-situ problems where the seepage flow analysis that does not follow the Darcy’s law is indispensable. A governing equation based on the nonlinear resistance law extending the Darcy’s law widely used in the previous models for seepage flow is employed in this model. The validation is conducted through experiments with soil layers in a laboratory scale.

Free Research Field

水資源システム工学

Academic Significance and Societal Importance of the Research Achievements

従来の浸透流解析モデルはダルシー則に基づく支配方程式によるものであり，その解析対象はダルシー流が前提である．本研究で改良を加え現場適用を検討した浸透流解析モデルは，ダルシー則を拡張した非線形抵抗則に基づく支配方程式によるものであり，ダルシー流および非ダルシー流を解析できるモデルである．また，近年，豪雨による土砂災害が毎年のように各地で発生していることを背景に，具体的な現場の問題として，豪雨時の山地斜面への降雨浸透流解析への適用可能性の検証に取り組んだ．