Article
Engineering, Marine
Zhimin Zhou, Yawei Sun, Lifen Chen, Dezhi Ning, Wojciech Sulisz
Summary: In this paper, a two-dimensional time-domain numerical flume is established to investigate the interactions between nonlinear surface waves and a submerged inclined thin plate. The study finds that the amplitude of the second-order harmonic free wave increases with the inclination angle of the plate and the wave steepness. Moreover, the amplitudes of both the second-order reflected and transmitted waves also increase with the wave steepness.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Civil
Dong-chuang Yuan, Yong Cheng, Chun-yan Ji
Summary: This study analyzed the fully nonlinear water entry of a cone into waves with gravity effect using a three-dimensional higher-order boundary element method. The use of image theory and modified Green function improved efficiency and accuracy in the calculations.
CHINA OCEAN ENGINEERING
(2021)
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
Engineering, Marine
Daniel Bar, Nitai Drimer
Summary: This study presents a numerical model called BELWF, which is used for the mathematical simulation of two-dimensional wave flumes. BELWF can simulate the hydrodynamics of wave shoaling over a coast profile, including submerged impermeable coastal structures of any geometry. The efficiency and validity of BELWF are confirmed through comparisons with OpenFOAM simulations.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Shi Yan Sun, G. X. Wu
Summary: This paper presents a higher order boundary element method (HOBEM) for inviscid flow passing a lifting body. By using higher order elements to discretize the body surface and applying a specific shape function to handle velocity variations near the trailing edge, the HOBEM is shown to be more accurate than the conventional BEM, especially for local results and velocity near the trailing edge.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Materials Science, Multidisciplinary
Maria Wilde, Maria Yu Surova, Nadezhda Sergeeva
Summary: This study focuses on the construction of refined boundary conditions for the case of edge loading, using a theory with modified inertia. By incorporating the works of Goldenveizer and Kolos, the three-dimensional problem solution is obtained through the superposition of long-wave approximation and boundary layers. The traction on the edge is represented by generalized Fourier expansions, employing Legendre polynomials. The resulting refined boundary conditions are able to satisfy the boundary conditions with minimal asymptotic error. The dispersion curve and amplitude of the edge wave calculated based on this modified inertia theory and refined boundary conditions demonstrate good agreement with the three-dimensional solution, surpassing the limitations of the Kirchhoff's theory. The study also explores the application of refined boundary conditions in the framework of two-dimensional theory, specifically for self-equilibrated edge loads.
MATHEMATICS AND MECHANICS OF SOLIDS
(2022)
Article
Engineering, Marine
S. Liang, B. Teng, Y. Gou
Summary: Based on potential flow theory, the interaction between nonlinear waves with infinite and finite elastic plates is examined. For infinite elastic plates, the singular phenomenon of second-order flexural-gravity waves is studied, while for finite elastic plates, the effects of plate length on the maximum second-order displacement and occurring frequency are investigated.
Article
Engineering, Marine
Ding Fu, Xizeng Zhao, Su Wang, Dongming Yan
Summary: This paper provides a new explanation for the wave dissipating mechanism of a heaving plate breakwater from the perspective of vortex kinematics. High-order finite difference method is used to numerically investigate the wave dissipating performance, showing that the heaving motion of the plate enhances the wave dissipating performance. The effects of plate width on the wave dissipating performance are also considered, with results indicating that a heaving plate breakwater is better for blocking medium and short waves.
Article
Engineering, Marine
Sung-Jae Kim, Moo-Hyun Kim, Weoncheol Koo
Summary: This study evaluates higher-order diffraction forces on vertical circular cylinders using a three-dimensional fully-nonlinear numerical wave tank (NWT). The results are compared systematically with experimental and perturbation-based numerical results, and the sensitivity of the NWT results to the orders of input waves is investigated. The increase of third-order sum-frequency force in shallow water long wave is noted.
Article
Engineering, Marine
Peiwen Cong, Bin Teng, Wei Bai
Summary: A numerical model was developed to simulate wave diffraction caused by an arbitrarily shaped structure in the presence of bi-directional incident waves, revealing that the presence of a vertical wall can significantly disturb the wave diffraction process from the cylinder, leading to greatly amplified second-order wave elevation within the region between the wall and cylinder.
Article
Engineering, Multidisciplinary
A. Abbasnia, K. Rezanejad, C. Guedes Soares
Summary: A two-dimensional fully nonlinear numerical wave flume is extended with a pneumatic model to compute the free surface flow inside the chamber of land-based Oscillating Water Column (OWC) devices. Potential theory and the Mixed Eulerian-Lagrangian method are used to calculate fluid flow, enhanced by a non-uniform rational B-Spline function. A pneumatic model is manipulated to obtain instantaneous air pressure on the chamber's free surface, with a focus on air compressibility in large-scale cases.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2021)
Article
Engineering, Marine
Sarat Chandra Mohapatra, C. Guedes Soares
Summary: A hydroelastic model is developed to study the characteristics of a floating flexible structure under oblique wave action. The effects of various design parameters and oblique wave incidence angle on the structural performance are analyzed through analytical and numerical methods.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Yi Zhang, Bin Teng
Summary: This paper presents a numerical investigation on the high-frequency wave loads and ringing responses of offshore wind turbine foundations exposed to steep waves. The results are verified by nonlinear wave diffraction problems and show satisfactory agreement with experimental data and theoretical solutions. The effects of peak frequency, input wave amplitude, and damping ratio on the ringing response of the foundations are discussed.
Article
Engineering, Civil
Shi-yan Sun, Jie Cui, Chao-ming Bao
Summary: A higher order boundary element method (HOBEM) is proposed for inviscid flow passing cylinders in bounded or unbounded domain. A new integral equation is derived for the tangential velocity, and the boundary is discretized into higher order elements to ensure continuity. The HOBEM is shown to be much more accurate than the conventional BEM through extensive comparison with analytical solutions for cylinders.
CHINA OCEAN ENGINEERING
(2023)
Article
Engineering, Marine
Eun-Hong Min, Weoncheol Koo, Moo-Hyun Kim
Summary: This study developed a two-dimensional fully nonlinear numerical wave tank (FN-NWT) to investigate the interaction between waves and dual submerged porous structures. It found that the FN-NWT can provide information on reflection and transmission coefficients, as well as wave deformation and force depending on porosity. The study applied the boundary element method (BEM) and incorporated Darcy's law or Forchheimer flow equation to model the flow in the porous domain. The results showed that the wave reflection coefficient of the porous structures agreed well with experimental data when using Forchheimer flow boundary conditions. However, excessive attenuation of the transmitted wave was observed when Darcy's condition was employed. The study also found that the difference in each coefficient due to the spacing of the submerged structures was reduced in the porous structure compared to the non-porous structure.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Marine
Cuiping Kuang, Jiadong Fan, Zhichao Dong, Qingping Zou, Xin Cong, Xuejian Han
Summary: A study on the mechanism of geomorphological evolution of a tidal lagoon reveals the importance of critical erosion and deposition shear stress, sediment settling velocity, and initial bed elevation in the formation and stability of tidal networks. The influence of initial bed elevation depends on the lowest tidal level. A Spearman correlation analysis suggests that critical erosion or deposition shear stress has a greater impact on geomorphological evolution than sediment settling velocity and initial bed elevation.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Ocean
Xuanlie Zhao, Qingping Zou, Jing Geng, Yang Zhang, Zhijie Wang
Summary: This study derived a semi-analytical solution from linear potential flow theory to investigate hydrodynamic characteristics of a rectangular oscillating water column array under oblique waves. The presence of along-shore sloshing resonance was found to decrease hydrodynamic efficiency and increase wave reflection, with the critical wavenumber being dependent on chamber length. Peak efficiency was observed at lower frequencies for larger incident wave angles, indicating that optimum coastal protection can be achieved by maximizing efficiency in the piston resonance frequency region.
APPLIED OCEAN RESEARCH
(2022)
Article
Engineering, Ocean
Zhiling Liao, Shaowu Li, Juan F. Paniagua-Arroyave, Ye Liu, Qingping Zou
Summary: Researchers have investigated the increase in energy flux of infragravity waves induced by shoals near Cape Canaveral. The results contribute to the understanding of nearshore hydrodynamics and can help mitigate coastal hazards.
APPLIED OCEAN RESEARCH
(2022)
Article
Engineering, Civil
Ye Liu, Yu Yao, Zhiling Liao, Shaowu Li, Chi Zhang, Qingping Zou
Summary: This study investigates the energy exchange between long waves and short-wave groups over a reef using fully nonlinear analysis. The results show that the fully nonlinear analysis yields different results compared to linear and weakly nonlinear analysis, highlighting the importance of considering nonlinear effects in wave transformation over reefs. The findings have implications for coastal inundation, structure stability, and sediment transport.
COASTAL ENGINEERING
(2023)
Article
Energy & Fuels
Yisheng Yao, Dezhi Ning, Sijia Deng, Robert Mayon, Ming Qin
Summary: With the siting of wind turbines moving from shallow water to deep sea, the stability of floating offshore wind turbines has become a major concern. This study proposes a new spar-buoy with a porous shell to improve platform stability. Numerical modeling and comparison with an existing spar are done to analyze motion response. The results show that the spar with the porous shell reduces motion response amplitudes, especially in heave motions, indicating its feasibility and potential for deep-sea offshore floating wind turbine development.
Article
Environmental Sciences
Jiadong Fan, Cuiping Kuang, Huixin Liu, Dan Wang, Jiantao Liu, Gang Wang, Qingping Zou
Summary: The recurrent green tide in Jinmeng Bay caused by the constructions of artificial islands and submerged reefs has severely damaged the coastal ecosystem. A numerical model was established to study the potential impacts of these constructions on water quality, showing that the tidal currents were hindered and tidal actions were weakened. As a result, the concentrations of COD and NO3- increased, leading to the frequent and large-scale green tides in Jinmeng Bay.
Article
Engineering, Marine
Di Mu, Lifen Chen, Dezhi Ning
Summary: This paper investigates the interaction between a three-dimensional dam-break flow and a vertical circular and square cylinder using OpenFOAM simulations. The findings have relevance and importance in coastal protections and offshore operations. The numerical model is validated against experimental measurements, and further examines the effects of geometry and impacting angle on the total impact load and flow field. The results reveal two distinct stages of the impact event and highlight the significant role of flow deflection in determining the pressure field and total force behaviors.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Marine
Cuiping Kuang, Jilong Chen, Jie Wang, Rufu Qin, Jiadong Fan, Qingping Zou
Summary: Oil spills pose a major threat to the marine ecosystem and have long-lasting effects on marine life and water quality. This study establishes a hydrodynamic and oil spill transport model of the Yangtze River Estuary, focusing on wind-wave-current interaction. The model accurately reproduces observed data and a real oil spill event during Typhoon Fongwong. The study reveals the influence of different weather conditions on oil particle trajectory and spread, providing valuable guidance for oil spill prevention and mitigation in other estuaries.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Marine
Sijia Deng, Ming Qin, Dezhi Ning, Lin Lin, Songxiong Wu, Chongwei Zhang
Summary: This paper investigates the non-linear wave loads and run-ups on an offshore wind turbine monopile foundation through numerical and experimental investigations. The experiment is conducted in a wave flume at the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, where wave loads and run-ups along the monopile are measured. The results show that the present non-linear potential theory is sufficient for simulating wave force and run-ups on the monopile before wave breaking. A W type distribution of wave run-up along the monopile is found, with the peak value occurring at the frontward side and two symmetrical minimum amplitudes at certain angles.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Ocean
Benjian Song, Cathal Cummins, Qingping Zou
Summary: Long-term cyclic loading on offshore wind monopiles can lead to a decrease in the mechanical properties of the seabed near the monopile's foundation, causing instability of the submarine slope and the monopile foundation. A numerical model showed that the safety factor of the slope significantly decreases with each stage of the process, and sharp changes in load amplitude and large average load also decrease the safety factors. An increase in monopile diameter and embedded depth can enhance overall slope stability.
APPLIED OCEAN RESEARCH
(2023)
Article
Engineering, Civil
Ye Liu, Shaowu Li, Zhiling Liao, Qi Liu, Qingping Zou, Weijie Liu
Summary: This study used tree-based models to identify the essential predictor parameters for runup in coral-reef environments and developed a set of runup formulae. It was found that wave conditions, reef roughness, and reef-flat length are crucial for predicting runup. The importance of forereef and beach slopes depends on the relative reef submergence. The proposed formula set was validated and has the potential for fast prediction of runup along coral-reef islands for flooding assessment.
COASTAL ENGINEERING
(2023)
Article
Engineering, Civil
Xin Cong, Cuiping Kuang, Guangwei Huang, Qingping Zou, Xuejian Han, Chao Shen, Jie Gu
Summary: A series of flume experiments using a mobile-bed sandbar-lagoon model were conducted to study the influence of vegetation density on wave attenuation and bed profile evolution. The experiments showed that wave attenuation increases with higher sandbar freeboard and vegetation density, while decreasing with lower incident wave height. Two types of fore-dune morphological evolution, collision and overwash, were observed. The maximum erosion thickness of dune has a quadratic relationship with vegetation density. The experimental results also emphasized the importance of wave height, water depth, sandbar freeboard, and vegetation density in the morphodynamic evolution of sandbar-lagoon systems.
COASTAL ENGINEERING
(2023)
Article
Mechanics
Zhiling Liao, Qingping Zou, Ye Liu, Stephanie Contardo, Shaowu Li
Summary: Short-wave group forcing is a major driving mechanism of infragravity waves. A unified solution is derived based on Green's function, which can describe the behavior of group-induced subharmonics under different resonance conditions in intermediate and shallow water.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Environmental Sciences
Cuiping Kuang, Jiadong Fan, Xuejian Han, Hongyi Li, Rufu Qin, Qingping Zou
Summary: This study investigates the effects of artificial reefs on beach profile evolution. The results show that artificial reefs enhance wave attenuation, reduce local flow velocity and offshore sediment transport, and thus protect the beach from wave erosion. The morphological evolution is more sensitive to water depth factor compared to equilibrium sediment concentration factor.
Article
Engineering, Ocean
Xuanlie Zhao, Fan Li, Jiachun Zhou, Jing Geng, Qingping Zou, Daqing Qin
Summary: This paper theoretically investigates a multi-resonant oscillating water column breakwater array, finding that multiple resonances in piston mode lead to increased hydrodynamic efficiency, broadening the effective frequency bandwidth with significant wave power absorption and coastal protection capability. However, resonances in sloshing mode weaken wave power extraction significantly in the alongshore direction.
APPLIED OCEAN RESEARCH
(2023)
