Article
Mathematics, Applied
Ruizhi Gong, Deng -Shan Wang
Summary: This study investigates the formation of undular bores in Riemann problems of the good generalized Kaup-Boussinesq equation using Whitham modulation theory. The Whitham equations associated with periodic wave solutions are derived using the finite-gap averaging method, and the self-similar solutions of the Whitham equations are used to analyze the basic structures of rarefaction waves and dispersive shock waves. A complete classification of all possible wave patterns for the initial discontinuity of the equation is proposed, and the agreement between the theoretical results from Whitham modulation theory and numerical simulations is demonstrated. The relationships between the soliton frontiers of the dispersive shock waves and the exact soliton solution of the equation are examined, leading to the discovery of exotic undular bores. The important physical applications of the theoretical results are demonstrated by exploring the dam break problem and piston problem, revealing previously unknown phenomena of wave breaking.
PHYSICA D-NONLINEAR PHENOMENA
(2022)
Article
Mechanics
Davide Wuthrich, Rui Shi, Hubert Chanson
Summary: Highly turbulent free-surface flows exhibit complex and rapidly changing air-water surface features, impacting environmental flows. A deeper understanding requires multiple repetitions and statistical analysis, as well as the use of optical flow techniques to characterize surface velocity fields.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Ecology
Ulung J. Wisha, Yusuf J. Wijaya, Yukiharu Hisaki
Summary: This study aims to reveal the physical characteristics and environmental impact of tidal bores in the Rokan Estuary. The study found that tidal bores in the upstream area have a higher amplitude and a shorter and more intense flood propagation. The height of the tidal bore in the estuary is approximately 3 meters and decreases by about 1 meter every 15 kilometers upstream. Turbulent velocities show a sharp increase at the end of the ebb tide and significantly decline when the tidal bore passes through the estuary.
REGIONAL STUDIES IN MARINE SCIENCE
(2022)
Article
Thermodynamics
Ying Li, Dongzi Pan
Summary: This study investigated the impact of tidal bores on a river-crossing bridge and derived empirical formulas for the maximum impact pressure in different areas. The results showed that the peak pressure of the instantaneous impulsive state of the bore can exceed the pressure of the quasi-steady state 10-fold.
ADVANCES IN MECHANICAL ENGINEERING
(2022)
Article
Environmental Sciences
Weiwei Song, Yi Li
Summary: This study investigated the ecological state of typical tidal flats along the eastern coast of China using field sampling, numerical simulation, and high-throughput sequencing. The findings revealed that the microbial communities in different subregions of the area exhibited notable differences due to variations in water quality and pollutant discharge. The study identified the impact of river pollutants on wetland microbial communities and established ecological patterns between the river and the sea, offering suggestions for watershed management and protection of coastal tidal flats.
ENVIRONMENTAL RESEARCH
(2023)
Article
Environmental Sciences
Preston Spicer, Zhaoqing Yang, Taiping Wang, Mithun Deb
Summary: This study investigates the impact of a tidal stream turbine array on tidal processes in an estuary. The results show that the turbine array can decrease tidal elevation and current magnitudes, reducing tidal asymmetry. This is attributed to the reduction in water volume between low and high waters, which weakens the nonlinear intertidal storage mechanism. Environmental considerations are also discussed.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Junbiao Tu, Daidu Fan, George Voulgaris
Summary: The study investigates turbulence dynamics and sediment suspension under intense tidal bore conditions at the Qiantang Estuary in China. The results show enhanced vertical mixing and suspended sediment distribution due to turbulence injection from surface breaking processes, leading to increased sediment transport. It also reveals that inward and outward interactions dominate at the early stage of the tidal bore, while sweep and ejection become important later on.
Article
Engineering, Civil
Tirtha Roy-Biswas, Dhrubajyoti Sen
Summary: This study investigates the tidal bore in the Hooghly estuary using field measurements and numerical modeling, revealing that the upper estuary experiences intense tidal bores despite damping effects. The study provides new estimates of bore intensity and explores the formation and evolution of the bore using a numerical model. The research also highlights the impact of riverbed asymmetry on bore appearances in natural estuaries.
JOURNAL OF WATERWAY PORT COASTAL AND OCEAN ENGINEERING
(2023)
Article
Engineering, Marine
Chengcheng Hou, Jianrong Zhu, Ju Huang, Xinyue Cheng
Summary: Estuaries are areas where runoff and tides interact, with tidal waves producing tidal currents and level variations along rivers. The positions of tidal current and level limits depend on both river discharge and river topography.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Ulung Jantama Wisha, Yusuf Jati Wijaya, Yukiharu Hisaki
Summary: This study provides real-time measurements of tidal bore properties in the Kampar River estuary, including tidal bore generation, hydraulic jump, and transport mechanism. The findings indicate that the estuary is influenced by semidiurnal co-tidal components and categorized as an ebb-dominant estuary. The tidal bore height decreases upstream, and the turbulent velocity is erratic. The passage of the bore results in increased sediment resuspension in the surrounding river edge.
Article
Marine & Freshwater Biology
David Salas-Monreal, Otilio Avendano, Jose de Jesus Salas-Perez, Mark Marin-Hernandez
Summary: The bidirectional flow pattern at the mouths of estuaries is influenced by tides, with inflows during high tide and outflows during low tide. However, during the rainy season, river discharge can change this flow pattern. In the Alvarado Estuary, river discharge from the Papaloapan River strongly stratified the water column at the estuary mouth, with temperatures related to the distance from the river. Suspended particles were concentrated in the deepest area of the estuary during flood tide periods, while water primarily exited through the estuary mouth and an artificial channel during ebb tide periods.
ESTUARINE COASTAL AND SHELF SCIENCE
(2023)
Article
Environmental Sciences
Xia Li, Yanzi Cai, Zezheng Liu, Xiaobiao Mo, Li Zhang, Cheng Zhang, Baoshan Cui, Ze Ren
Summary: This study analyzed long-term observational data to investigate the variability of tidal dynamics in the Pearl River Estuary. The results showed significant spatial-temporal variability in tidal variables, which were influenced by estuarine geomorphology, river discharge, and sea-level rise.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Phyo Zaw Oo, Suwanna Kitpati Boontanon, Narin Boontanon, Shuhei Tanaka, Shigeo Fujii
Summary: The research investigated the levels and variations of microplastics pollution in the Chao Phraya River Estuary and found that the abundance of microplastics was directly related to tidal fluctuations, leading to accumulation in certain areas. Polypropylene, polyethylene, and polystyrene were the most common polymers found in the estuary.
MARINE POLLUTION BULLETIN
(2021)
Article
Geosciences, Multidisciplinary
Dongfeng Xie, Zheng Bing Wang, Junbao Huang, Jian Zeng
Summary: Understanding tidal dynamics in estuaries is crucial for tidal predictions and assessments of sediment transport. This study analyzes the multiple-timescale tidal dynamics in the Qiantang Estuary and finds that tidal amplification is stronger during spring tide in the upper estuary. Seasonal and interannual variations in water levels depend on local bathymetrical conditions. The relationship between tidal ranges and depth is significant in the upper estuary.
Article
Engineering, Civil
Wang Qiu-shun, Pan Cun-hong, Chen Fu-yuan
Summary: This study explores the hydrodynamic phenomenon of tidal bore propagation around a similar right-angle shoreline. The characteristics of tidal bore propagation are investigated using a hydrodynamic model and theoretical methods, highlighting the intensity of tidal bores and the formation of back-flow bores. The model results show good agreement with field data, providing insights into the dynamics of tidal bores near the similar right-angle shoreline.
CHINA OCEAN ENGINEERING
(2022)
Article
Environmental Sciences
Mattia Pivato, Luca Carniello, Daniele Pietro Viero, Chiara Soranzo, Andrea Defina, Sonia Silvestri
Article
Environmental Sciences
Riccardo Alvise Mel, Daniele Pietro Viero, Luca Carniello, Luigi D'Alpaos
Article
Water Resources
Riccardo A. Mel, Daniele P. Viero, Luca Carniello, Luigi D'Alpaos
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2020)
Article
Marine & Freshwater Biology
Riccardo A. Mel, Daniele P. Viero, Luca Carniello, Andrea Defina, Luigi D'Alpaos
Summary: The closure of the Venice Lagoon in October 2020 for the first time in history due to the Mo.S.E. system's operation not only prevented flooding but also led to unprecedented hydrodynamic scenarios. The closure facilitated a better understanding of wind effects on tide propagation, as well as the evaluation of gate operations' impact on seaward disturbance and infiltration into the lagoon.
ESTUARINE COASTAL AND SHELF SCIENCE
(2021)
Article
Engineering, Civil
Tommaso Lazzarin, Daniele P. Viero, Daniela Molinari, Francesco Ballio, Andrea Defina
Summary: In this paper, a physics-based method for assessing flood damage is proposed. A non-dimensional impact parameter is introduced to combine water depth and flow velocity, which allows for evaluating relative damage functions for items of different nature. This method provides an understandable assessment of flood hazard even with limited data.
JOURNAL OF HYDROLOGY
(2022)
Article
Multidisciplinary Sciences
Davide Tognin, Alvise Finotello, Andrea D'Alpaos, Daniele P. Viero, Mattia Pivato, Riccardo A. Mel, Andrea Defina, Enrico Bertuzzo, Marco Marani, Luca Carniello
Summary: Coastal flooding prevention measures, such as storm-surge barriers, are widely adopted globally due to rising sea levels. However, their effects on shallow tidal embayment morphodynamics are poorly understood. Field data and modeling results from the microtidal Venice Lagoon reveal that artificial reduction of water levels leads to increased sediment resuspension and decreased salt marsh accretion.
Article
Water Resources
Tommaso Lazzarin, Daniele P. Viero
Summary: In this study, helical flow secondary currents are included in a two-dimensional depth-averaged hydro-morphodynamic model to analyze the flow field and bed evolution near bends. Different methods are compared in terms of their impact on the flow field and bed evolution using data from laboratory experiments and real-world case studies. The study also discusses key factors in secondary flow modeling, such as implementation tricks and mesh design guidelines.
ADVANCES IN WATER RESOURCES
(2023)
Article
Geosciences, Multidisciplinary
A. Ielpi, D. P. Viero, M. G. A. Lapotre, A. Graham, M. Ghinassi, A. Finotello
Summary: River meandering controls the age of floodplains through the formation of oxbows, while the spacing and timescales of bend evolution and abandonment can be used to constrain the distribution of floodplain ages and sediment-storage time. This approach applies to both natural and simulated rivers, suggesting its potential applicability to unconfined meandering rivers in other locations. However, further testing with independent geo- or dendrochronological data is required.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Engineering, Civil
Tommaso Lazzarin, Daniele P. Viero, Daniela Molinari, Francesco Ballio, Andrea Defina
Summary: Commonly adopted procedures for flood damage assessment have limitations in describing the time evolution of hazard and exposure during the flood event. This study proposes a new framework that considers how flood damage evolves in time, showing potential for flood risk assessment and management.
JOURNAL OF HYDROLOGY
(2022)
Article
Mechanics
Tommaso Lazzarin, Daniele Pietro Viero, Andrea Defina, Luca Cozzolino
Summary: The present paper focuses on two unresolved issues in the free orifice flow under vertical sluice gates: flow stability at large gate openings and the determination of multiple solutions in the case of partial dam-break. Through laboratory experiments and numerical simulations, utilizing a computational fluid dynamics model with the volume of fluid method, these interconnected problems are investigated. A series of quasi-steady states is utilized to determine the threshold of relative gate openings for the transition from orifice flow to non-interacting flow. Furthermore, dam-break experiments with partial gate opening are conducted to establish reliable criteria for disambiguating multiple exact solutions provided by the one-dimensional shallow water theory.
Article
Mechanics
Daniele Pietro Viero, Tommaso Lazzarin, Paolo Peruzzo, Andrea Defina
Summary: The study proposes and discusses a theoretical approach to predict the behavior of open-channel supercritical flow passing over a non-orthogonal step. A sequence of oblique shock waves and expansion fans is generated near and downstream of the step. The proposed model is validated by comparing with a numerical model. Applications include using oblique steps and abrupt wall deflections to control wave fronts in channel bends. Special attention is given to the transition from supercritical to subcritical flow over a forward-facing step, which exhibits complex solutions and hysteresis effects. The theoretical and numerical models determine the existence and hysteresis domains of different flow configurations.
Article
Environmental Sciences
T. Lazzarin, G. Constantinescu, L. Di Micco, H. Wu, F. Lavignani, M. Lo Brutto, D. Termini, D. P. Viero
Summary: The present study investigates the impact of bed roughness on flow and turbulence structure around an isolated, partially-buried mussel. The results show that increasing bed roughness amplifies turbulence kinetic energy in the near-wake region and weakens the strength of the main downwelling flow.
WATER RESOURCES RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Tommaso Lazzarin, Andrea Defina, Daniele Pietro Viero
Summary: The present work aims to assess the change in flood risk over time due to landscape modifications. The town of San Dona di Piave (Italy) is used as a case study, as it has experienced significant urbanization and anthropization in recent decades, similar to other floodplains in Northern Italy. Flood damage to residential buildings is used as a proxy for flood risk. The analysis is conducted at a local scale, considering changes to individual buildings, and utilizes GIS data such as high-resolution topography, technical maps, and aerial images to track the evolution of the landscape in terms of urbanized areas and hydraulic structures. A physics-based hydrodynamic model is used to determine flood hazard, while an innovative method is employed to estimate the expected flood damage to residential buildings. The findings demonstrate the detrimental effect of urbanization on flood risk, with the risk increasing in proportion to the extent of urbanized areas. The study also highlights the time evolution of flood damage within individual flood events, reflecting changes in the flooding process. Overall, this research offers a promising technique for analyzing the effects of past landscape changes on flood risk, and provides a valuable tool for informed and sustainable land planning.