Development of seamless tsunami and storm surge inundation model using adaptive mesh refinement

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K06577
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Hydraulic engineering
• Research Institution: Hiroshima University
• Principal Investigator: Lee Han Soo 広島大学, 先進理工系科学研究科(国), 准教授 (10535082)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: seamless model / adaptive mesh refinement / tsunami / storm surge / AMR

Outline of Final Research Achievements

In numerical modelling for long-waves such as tsunamis and storm surges, a nesting method that simultaneously calculates multiple regions with different spatial resolutions is common. However, this method has the drawbacks of requiring a large calculation load and calculation time, as well as numerical error and numerical instability. Adaptive mesh refinement subdivides the grid only in places that require high spatial resolution, so it is possible to improve calculation accuracy, improve calculation efficiency, and significantly reduce calculation time. In this study, a seamless inundation model that can collectively calculate from the disaster external force generation part of tsunami / storm surge to the inundation considering complex topography and detailed structures in the land run-up and coastal / river downstream part is developed by using adaptive grid refinement to improve the accuracy and efficiency of tsunami and storm surge numerical modellings.

Free Research Field

水工学，海岸工学

Academic Significance and Societal Importance of the Research Achievements

①津波・高潮モデルは物理過程の解明のための高解像度化・高精度化と迅速な予報のための効率化が要求される．しかし，計算結果における精度と計算に要する負荷・効率の両面からの必要に応じることが出来る代案はまだないと言える．本研究では，適合格子細分化を用い，災害外力発生部から沿岸・河川下流部の詳細地形や構造物を考慮した越流や氾濫まで一つの計算領域で計算可能なシームレス氾濫モデルを開発し，ネスティング手法の対案として提案した．また，適合格子細分化による河川の氾濫や洪水においてリアルタイム予測も現実的である．さらに，計算環境が十分に整っていない途上国の防災・減災における重要なツールとして貢献できる．