Towards a unified drag coefficient formula for quantifying wave energy reduction by salt marshes
Towards a unified drag coefficient formula for quantifying wave energy reduction by salt marshes
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建立统一的阻力系数公式来量化盐沼减少的波浪能量
DOI：
10.1016/j.coastaleng.2022.104256
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发表时间：
2023
影响因子：
4.4
通讯作者：
Johnson, Bradley D.
中科院分区：
文献类型：
--
作者：
Zhu, Ling;Chen, Qin;Ding, Yan;Jafari, Navid;Wang, Hongqing;Johnson, Bradley D.
在气候变化的背景下，沿海地区容易遭受日益增加的洪水风险。沿海湿地在减轻沿海灾害方面发挥着重要作用。植被对水流施加阻力，抑制风暴潮和风浪。植被对波浪衰减的预测通常依赖于预先确定的阻力系数C D 。现有的C D 公式受植被生物力学特性的影响，尤其是灵活性。通过有效植物高度（EPH）来考虑植被灵活性，我们基于涵盖广泛的水动力条件和植被性状的三个独立数据集提出并验证了 C D 和雷诺数 Re 之间的与物种无关的关系。所提出的 CD−Re 关系与 EPH 一起使用，可以高精度预测盐沼中的波衰减。此外，使用所提出的 CD−R e 关系和 EPH 进行了总共 308,000 次不同波浪条件的数值实验，以量化两种典型盐醪物种的波浪衰减能力：披碱草（高度柔性）和互花米草（相对刚性）。研究发现，波浪衰减受波高与水深比和EPH与水深比控制。当在浅水到中水深度的大波浪中摇摆时，50米长的披碱草场可能会失去高达30%的波浪衰减能力。随着波高的增加，高度灵活的植被会导致波衰减减少，而相对刚性的植被会导致波衰减增加。叶片对波衰减的贡献高度依赖于叶片刚度。建议在未来的现场实验中收集叶片特性，特别是杨氏模量。
Coastal regions are susceptible to increasing flood risks amid climate change. Coastal wetlands play an important role in mitigating coastal hazards. Vegetation exerts a drag force to the flow and dampens storm surges and wind waves. The prediction of wave attenuation by vegetation typically relies on a pre-determined drag coefficient C D. Existing C D formulas are subject to vegetation biomechanical properties, especially the flexibility. Accounting for vegetation flexibility through the effective plant height (EPH), we propose and validate a species-independent relationship between C D and the Reynolds number R e based on three independent datasets that cover a wide range of hydrodynamic conditions and vegetation traits. The proposed C D− R e relationship, used together with EPH, allows for predicting wave attenuation in salt marshes with high accuracy. Furthermore, a total of 308,000 numerical experiments with diverse wave conditions are conducted using the proposed C D− R e relationship and EPH to quantify the wave attenuation capacity of two typical salt mash species: Elymus athericus (highly flexible) and Spartina alterniflora (relatively rigid). It is found that wave attenuation is controlled by wave height to water depth ratio and EPH to water depth ratio. When swaying in large waves in shallow to intermediate water depth, a 50-m-long Elymus athericus field may lose up to 30% capacity for wave attenuation. As wave height increases, highly flexible vegetation causes reduced wave attenuation, whereas relatively rigid vegetation induces increased wave attenuation. The leaf contribution to wave attenuation is highly dependent on the leaf rigidity. It is recommended that leaf properties, especially its Young’s modulus be collected in future field experiments.
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影响因子：
4.4
作者：
Lei, Jiarui;Nepf, Heidi
通讯作者：
Nepf, Heidi
Juan L. Garzon、Tyler Miesse 和 Celso M. Ferreira 讨论“风暴条件下切萨皮克湾沼泽中波浪传播的现场数值模型研究”
影响因子：
4.4
作者：
Ling Zhu;Q. Chen
通讯作者：
Q. Chen
DOI：
10.5194/hess-2016-225-rc1
发表时间：
2016
期刊：
--
影响因子：
--
作者：
N. Ganju;Z. Defne;M. Kirwan;S. Fagherazzi;A. D’Alpaos;L. Carniello
通讯作者：
N. Ganju;Z. Defne;M. Kirwan;S. Fagherazzi;A. D’Alpaos;L. Carniello
影响因子：
4.4
作者：
T. V. Veelen;T. P. Fairchild;D. Reeve;H. Karunarathna
通讯作者：
T. V. Veelen;T. P. Fairchild;D. Reeve;H. Karunarathna
影响因子：
3.3
作者：
Chakrabarti, Agnimitro;Chen, Qin;Liu, Don
通讯作者：
Liu, Don