日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

セッション記号 A (大気水圏科学) » A-HW 水文・陸水・地下水学・水環境

[A-HW23] 水循環・水環境

2019年5月29日(水) 15:30 〜 17:00 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:町田 功(産業技術総合研究所地質調査総合センター)、山崎 大(東京大学生産技術研究所)、林 武司(秋田大学教育文化学部)、福士 圭介(金沢大学環日本海域環境研究センター)

[AHW23-P10] Hydraulic analysis of overland flow caused by temporally varying rainfall

*PING-CHENG HSIEH1Ming-Chang Wu1 (1.National Chung Hsing University)

キーワード:overland flow, nonuniform rainfall, diffusion wave

With the development of human civilization and population migration, we use many different types of pervious or impervious materials to cover the original surface. As a result, the surface friction and water permeability are reduced, resulting in increased flow velocity and runoff, and thus increasing the frequency and scale of flood occurrence. Therefore, predicting changes in overland flow caused by rainfall has become an important issue.

This study intends to simulate the overland flow under different rainfall patterns by the theory of diffusion wave model. The diffusion wave equation was used as the governing equation, and an analytical solution of the water depth by the generalized integral transformation method was presented. Since the values of the parameters used in previous research for diffusion wave models vary in an extensive range. In this study, the parameters were adjusted for each location to ensure the rationality of the simulation results according to the law of mass conservation.
The results show that for the non-uniform rainfall, the peak water depth and peak flow due to the post-peak rainfall are the largest, followed by the third quarter peak rainfall; whereas the average flow velocity of the mid-peak rainfall is the largest, followed by the third quarter peak rainfall. The peak water depth, peak flow rate and average flow rate due to the double peak rainfall are the smallest among the six rainfall patterns in this study.