Article
Water Resources
R. Familkhalili, N. Tahvildari
Summary: A two-way fully coupled hydrodynamic-vegetation model was developed, successfully validated against laboratory experiments and further used to study the effects of vegetation on wave dynamics. The incorporation of a new mechanism for flexible vegetation in the wave model resulted in improved simulation results compared to rigid vegetation models.
ADVANCES IN WATER RESOURCES
(2022)
Article
Engineering, Marine
Kai Yin, Sudong Xu, Shangpeng Gong, Runpu Zhou, Yiran Wang
Summary: This study quantitatively determined the effects of wave nonlinearity on submerged flexible vegetation dynamics and wave attenuation based on flexible vegetation dynamic model and experimental results. It also evaluated the influence of different wave theories and determination methods of characteristic wave velocity quantitatively. Results showed that wave nonlinearity exerts substantial effects on flexible vegetation dynamics and wave attenuation rate.
Article
Engineering, Marine
Kai Yin, Ming Lin, Sudong Xu, Jianxin Hao, Liuyan Mao, Mengqi Li
Summary: This study aims to extend the application range of numerical models to investigate the dynamics of flexible vegetation and wave attenuation under combined waves and currents. By comparing with experimental measurements, the reliability of numerical methods in simulating flexible vegetation dynamics and wave attenuation under combined waves and following currents is confirmed. The results reveal that the Keulegan-Carpenter number and velocity ratio have significant nonmonotonic effects on the dynamics of flexible vegetation, and the presence of following currents can enhance or suppress wave attenuation depending on the velocity ratio and water depth.
Article
Engineering, Marine
Kai Yin, Sudong Xu, Shangpeng Gong, Jie Chen, Yiran Wang, Mengqi Li
Summary: This study extends the XBeach phase-averaged wave model to simulate wave attenuation by both homogeneous and heterogeneous submerged flexible vegetation, and determines the simulation deviation based on different wave theories. The reliability of the coupled model in simulating wave attenuation by flexible vegetation is revealed. The study demonstrates that the computed wave attenuation rate based on Stokes second-order wave theory is larger than that based on linear wave theory, and the deviation between these two wave theories increases as the Ursell number increases.
Article
Engineering, Ocean
Xuebin Chen, Guoji Xu, Zhiwu Chen, Ling Zhu, Shuqun Cai
Summary: Internal waves are a type of wave phenomenon that can traverse the depth of the ocean, and they pose safety challenges and threats to submarine structures. This study proposes a numerical model to analyze the nonlinear interaction between depression internal solitary waves and submerged floating tunnels (SFTs) in stratified fluids. The hydrodynamic model is verified and used to simulate the interaction between internal waves and SFTs under various conditions. The simulation results show that wave forces and motion responses are closely related to the submergence, wave amplitude, and density ratio, and the presence of mooring lines can significantly reduce the motion displacements of the SFTs.
APPLIED OCEAN RESEARCH
(2023)
Article
Thermodynamics
Pengbo Wei, Jingyu Li, Weixiong Chen, Daotong Chong, Junjie Yan
Summary: The vigorous progress of nuclear industry under marine environment poses challenges to the security and steady operation of steam submerged jets. Experimental investigation shows that heave motion affects the pressure oscillation phenomenon and steam bubble morphology. Furthermore, an experimental correlation is proposed to predict the dominant frequency in heave motion.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Marine
Shuo Liu, Sudong Xu, Kai Yin
Summary: This study investigates the impact of submerged rigid and flexible vegetation on wave attenuation using experimental and numerical approaches. The influence of wave conditions and vegetation characteristics on wave attenuation was accurately reproduced by adjusting the drag coefficients within the numerical model. It was found that wave nonlinearity plays a significant role in wave attenuation, especially in the presence of rigid vegetation.
Article
Environmental Sciences
Yue Yuan, Xiaobing Chen, M. Bayani Cardenas, Xiaofeng Liu, Li Chen
Summary: The interaction between flow and vegetation plays a significant role in affecting fluid dynamics and material transport in river corridors. This study conducted numerical models to investigate vegetation-induced hyporheic exchange and found that vegetation can increase hyporheic flux through relatively shallower exchange zones compared to bedform-induced flow. The results were synthesized into predictive models for hyporheic flux, bulk residence time, and exchange depth based on drag coefficient, vegetation density, and Reynolds Number.
WATER RESOURCES RESEARCH
(2021)
Article
Engineering, Marine
Elpidoforos Repousis, Ioannis Roupas, Constantine Memos
Summary: This study focuses on predicting the technical efficiency of narrow-crested submerged permeable rubble-mound breakwaters in terms of wave attenuation. Through physical modelling and data analysis, it was found that the wave breaking mechanism significantly affects wave energy dissipation and can be directly linked to the wave transmission coefficient for a given structure's geometry and sea state.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Environmental Sciences
D. G. Gundersen, K. T. Christensen, G. Blois
Summary: This study presents an experimental protocol to quantify the interaction between structural deformation of fluvial vegetation canopies and fluid flow. High-speed particle image velocimetry data and corresponding solid displacement field were obtained using fluorescent imaging and refractive index matching. The time-resolved data enables observation of the dynamic link between a deformable object and the surrounding flow field.
WATER RESOURCES RESEARCH
(2022)
Article
Engineering, Marine
Weidong Chen, Chao Wang, Bing Ren, Pengzhi Lin
Summary: The experimental investigations into the motion characteristics of a twin-circular submerged floating tunnel under wave actions were conducted. The study found that the resonance motion with half of the incident wave frequency and a large amplitude would be excited when the incident wave frequency was close to twice the natural frequency of the structure. This resonant sway motion, caused by the Mathieu instability, poses a threat to the traffic safety of the submerged floating tunnel.
Article
Environmental Sciences
Z. Hu, S. Lian, T. Zitman, H. Wang, Z. He, H. Wei, L. Ren, W. Uijttewaal, T. Suzuki
Summary: This study reveals and quantifies the wave breaking process induced by opposing currents in vegetated flows, which was not reported before. The results show that current-induced breaking constitutes a significant part of total dissipation in submerged canopies. This study improves our understanding of vegetation wave dissipation capacity in field conditions.
WATER RESOURCES RESEARCH
(2022)
Article
Biodiversity Conservation
Douglas Monteiro Cavalcante, Maria Tatiane Leonardo Chaves, Gabriella Moreira Campos, Jose Ramon Barros Cantalice, Genival Barros Junior
Summary: This study investigated the impact of flexible vegetation elements of Ipomoea pes-caprae species on water flow and sediment transport capacity. Results showed that aquatic vegetation directly influences river dynamics, with vegetation density having an impact on flow transport capacity. As the vegetation drag coefficient increases, it enhances the resistance to flow and reduces sediment transport capacity.
ECOLOGICAL INDICATORS
(2021)
Article
Engineering, Marine
Wenbo Pan, Meng He, Cheng Cui
Summary: The dynamic responses of a two-dimensional submerged floating tunnel (SFT) under random and freak waves were studied. The results show that the dynamic responses of the SFT under freak waves are significantly larger than those under other waves, especially in terms of motion response. The amplification coefficients of surge, heave, and pitch increase nonlinearly with the increase of the freak wave parameter. The amplification coefficients of tension show a linear increase. The amplification effect of the freak wave on motion responses is greater than that on the mooring tension. The growth rates of motion responses under the freak wave exceed the growth rates for maximum wave height.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Environmental Sciences
Hayoon Chung, Tracy Mandel, Francisco Zarama, Jeffrey R. Koseff
Summary: The study shows that gaps in submerged vegetation enhance turbulence locally, but also introduce enhanced turbulent energies throughout the water column that are transported downstream, perturbing the canopy flow. A scaling equation was proposed to predict if turbulence perturbations induced by an upstream gap will influence the turbulence at a given distance downstream.
WATER RESOURCES RESEARCH
(2021)
