Quasi-3D model for undular-hydraulic jump and hydraulic jump

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K13839
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22040:Hydroengineering-related
• Research Institution: Chuo University
• Principal Investigator: Takemura Yoshiharu 中央大学, 研究開発機構, 機構准教授 (90634684)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: 波状跳水 / 完全跳水 / 準三次元解析 / 非静水圧分布 / Q3D-FEBS / 河川構造物 / バッフルピア

Outline of Final Research Achievements

This paper aims at development of a non-hydrostatic quasi-three dimensional model for the flow in undular and hydraulic stilling basins. It is challenging for the depth-integrated model to calculate the flow separation at boundary surfaces (water surface and bed surface). To solve this problem, a non-hydrostatic quasi-three dimensional model considering flow equations on boundary surfaces (Q3D-FEBS) was derived. Q3D-FEBS was applied to the undular and hydraulic jump experiments. The calcula-tion results are in good agreement with the observation data such as water surface profiles and velocity distributions of the undular and hydraulic jump. Moreover, it was showed that Q3D-FEBS can calculate the breaking process of the undular jump and, formation of the surface roller. Finally, the applicability of Q3D-FEBS for the flow in hydraulic jump stilling basins was discussed against observation data of a large scale hydraulic model experiment.

Free Research Field

水工学

Academic Significance and Societal Importance of the Research Achievements

本研究で提案した非静水圧準三次元解析法(Q3D-FEBS)は，水深積分モデルの枠組みにおいて，波状跳水と完全跳水，さらに水理条件の変化に伴う跳水形態の遷移について，国内外で初めて解析可能とした．また，Q3D-FEBSは，三次元解析に比べ基礎方程式の数は増えるものの，鉛直方向の格子分割が不要なことに加え，全ての方程式が陽的に解析されるため，三次元解析に比べて計算コストを著しく節約できる．今後，大型越流構造物周辺の三次元流れを検討するための有効な手法として活用が期待される．