A NUMERICAL MODEL OF WAVE-RUN-UP AND RESULTING LONGSHORE SEDIMENT TRANSPORT DUE TO OBLIQUELY INCIDENT WAVE

波浪爬升及斜入射波引起的沿岸沉积物输送的数值模型

• 批准号: 08455227
• 负责人: ISOBE Masahiko
• 金额: $ 4.03万
• 依托单位: THE UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455227/
• 关键词: Coast; Swash zone; Sedimentation; Longshore sediment transport; Wave

Swash zone dynamics is an important factor in computing longshore sediment transport rate. In the present study, a numerical model is developed to predict the onshore distribution of the longshore sediment transport rate by taking into account the moving shoreline boundary condition.Boussinesq-type equations were adopted as the governing equations that include non-linearity and dispersivity, and a breaking model was incorporated. The longshore coordinate and the time were combined into one independent variable under the assumption of a uniform water depth in the longshore direction. The offshore boundary condition included the radiation boundary condition which can absorb the outgoing waves ; the onshore boundary condition was developed to reproduce the moving shoreline in the swash zone.We applied this model to the numerical computations with obliquely incident waves to simulate wave kinetics including swash motion, and found that the model can reproduce the moving shoreline as well as wave deformation and breaking correctly.In addition to the wave field, the nearshore current field was modeled by considering the bottom friction. By incorporating the sediment transport formula proposed by Dibajnia and Watanabe (1994), the model resulted in a bi-modal distribution, with one peak around the breaking point and the other around the shoreline, which has been recognized in the laboratory experiment.As a result, a general numerical model for obliquely incident waves on the bottom topography of straight and parallel offshore contours is developed, which can reproduce non-linear wave deformation, swash motion, longshore current, and onshore distribution of the longshore sediment transport rate

冲刷带动力学是计算沿岸沉积物输送速率的重要因素。在本研究中，建立了一个数值模型，通过考虑移动海岸线边界条件来预测沿岸泥沙输送速率的陆上分布。采用Boussinesq型方程作为包含非线性和分散性的控制方程，并结合了破碎模型。在沿岸方向水深均匀的假设下，将沿岸坐标和时间合并为一个自变量。近海边界条件包括吸收出波的辐射边界条件；开发了陆上边界条件来再现斜流区的移动海岸线。我们将该模型应用于斜入射波浪的数值计算中，以模拟包括斜流运动在内的波浪动力学，发现该模型可以正确再现移动的海岸线以及波浪的变形和破碎。除了波场之外，还考虑了底部摩擦力来模拟近岸流场。通过结合 Dibajnia 和 Watanabe (1994) 提出的泥沙输运公式，该模型产生了双峰分布，一个峰值围绕断裂点，另一个峰值围绕海岸线，这一点在实验室实验中得到了认可。因此，建立了一种用于直和平行离岸等高线底部地形斜入射波的通用数值模型，该模型可以再现非线性波 变形、斜流运动、沿岸流和沿岸沉积物输送率的陆上分布

项目成果

田島芳満・磯部雅彦・渡辺 晃・横木裕宗: "非線形緩勾配方程式を用いた砕波限界に関する数値的研究" 海岸工学論文集. 43. 277-281 (1996)

Yoshimitsu Tajima、Masahiko Isobe、Akira Watanabe、Hiromune Yokogi：“使用非线性缓坡方程进行波浪破碎极限的数值研究”海岸工程学报 43. 277-281 (1996)。

有川太郎・磯部雅彦: "染色体緩勾配方程式を用いた砕波判定法の適用性" 海岸工学論文集. 44. 91-95 (1997)

有川太郎和矶部正彦：“利用染色体慢梯度方程确定波浪破碎方法的适用性”海岸工程杂志 44. 91-95 (1997)。

磯部雅彦,渡辺晃,中村裕史: "斜め入射波の遡上とそれに伴う浜漂砂の数値モデル" 海岸工学論文集. 44. (1997)

Masahiko Isobe、Akira Watanabe、Hiroshi Nakamura：“倾斜入射波的上升和相关海滩沙流的数值模型”海岸工程杂志 44。（1997 年）。

中村裕史・渡辺 晃・磯部雅彦: "斜め入射波の遡上とそれに伴う浜漂砂の数値モデル" 土木学会年次学術講演会講演概要集第2部. 52. 132-133 (1997)

Hiroshi Nakamura、Akira Watanabe 和 Masahiko Isobe：“倾斜入射波的上升和海滩上相关沙流的数值模型”，日本土木工程师学会年度学术会议讲座摘要第 2.52.132-133 部分（1997 年） ）

山下淳平,M.Djbajnja,渡辺晃: "不規則波浪下でのシートフローによる漂砂量算定式" 海岸工学論文集. 43. 476-480 (1996)

Junpei Yamashita、M. Djbajnja、Akira Watanabe：“基于不规则波浪下的面流计算沙流量的公式”海岸工程杂志 43. 476-480 (1996)。