CERES :: Browsing by Author "Huang, Luofeng"

Browsing by Author "Huang, Luofeng"

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Open Access
A comparative experimental study on the hydrodynamic performance of two floating solar structures with a breakwater in waves
(Elsevier, 2024-12) Yang, Yifeng; Mi, Chenhao; Ou, Binjian; Wong, Anson; Duffy, John Gordon; Wood, Tim; Utama, IKAP; Chen, Wenchuang; Huang, Luofeng
Floating Photovoltaic (FPV) is considered as a highly promising clean energy solution. In recent years, FPV has been widely deployed in calm water around the world. However, to find available space for further expansion, FPV needs to be deployed in seas whilst the oceanic waves significantly influence the structural stability and energy performance. On one hand, wave loads may cause structural fatigue and damage. On the other hand, wave-induced rotations of a floating solar panel will vary its tilt angle to the sunlight and thus affect the power output. To explore the new research field of ocean-based FPV, this work first designed a novel catamaran FPV floater with a four-point mooring system. Comparative experiments were then conducted in a wave tank to compare its seakeeping ability with a conventional flat-plate floater. Besides, a breakwater structure was further introduced to enhance the stability of these two types of floaters. Detailed data on floater motions and mooring line forces were collected under monochromatic wave conditions. Extensive analysis was performed to evaluate the wave-mitigating performance of the breakwater, as well as the nonlinearity in the motion and force time histories. Overall, the work provides valuable experimental data and novel insights into the design of FPV floaters and breakwater protection, supporting long-term sustainability of FPV on the ocean.
Open Access
A study into the correlation between single array-hull configurations and wave spectrum for floating solar photovoltaic systems
(Elsevier, 2024-11-15) Jifaturrohman, Mohammad Izzuddin; Utama, I Ketut Aria Pria; Putranto, Teguh; Setyawan, Dony; Huang, Luofeng
Floating photovoltaic (FPV) systems offer a viable renewable energy solution due to easy installation and cost-effectiveness compared to other renewable energy generation methods. On the other hand, land-based solar photovoltaics face challenges such as space scarcity and environmental impacts. Shifting to nearshore locations unlocks vast ocean space potential, though waves expose significant challenges to FPV systems. Several novel FPV system designs are proposed, inspired by high-speed vessel multihulls, including catamaran, trimaran, quadrimaran, and pentamaran configurations, as floating supports for solar panels. Simulations were conducted to determine Response Amplitude Operators (RAOs) under various irregular wave spectrum conditions in a free-floating initial state. The FPV motion problem was solved using linear potential-flow theory with the Boundary Element Method (BEM) with Green-Function approach. Superposition of wave spectral energy and motion RAOs was used to obtain spectral structural responses. Motion in heave, roll, and pitch modes was evaluated across wave spectrum types. Results show that adding hulls reduces the significant amplitude response in all motion modes. In summary, valuable insights into floater designs and the hydrodynamic evaluation of FPV systems are presented.
Open Access
A study into the effect of Hull Configuration on the performance of floating solar PV structure
(Akademia Baru Publishing, 2024-11-30) Jifaturrohman, Mohammad Izzuddin; Utama, I Ketut Aria Pria; Putranto, Teguh; Setyawan, Dony; Huang, Luofeng
At present, energy transition is a reality in the journey towards achieving net zero emission. Among others, the development of floating solar photovoltaic (FPV) power plants is one of many possible renewable energy technologies that received considerable attention. One of the reasons for that is attributed to land acquisition which can lead to conflicts, whilst the use of sea is more flexible. Therefore, the development of floating solar PV situated at the near shore (later can be moved offshore) is promising particularly in order to withstand the harsh environment. The study aims to demonstrate such an innovative design of a floating structure and two types of hulls (monohull and twin-hull) are considered and focused on the seakeeping performance of the two bodies. BEM approach with Green-Function based on the 3-D diffraction panel method together with the use of the Joint North Sea Wave Project (JONSWAP) wave spectrum is carried out to accomplish the seakeeping characteristic. The final computational simulation results show that the twin-hull model has more advantages than the monohull design. The trend of the RAO pattern, response spectra, and significant response for heave and pitch motion represent only slight differences between the two proposed designs. However, substantial disparity emerges in roll motion, with the difference in response values in prevailing 0o -roll heading standing at 53%, 39%, 27%, and 18% for sea states 1 through 4, respectively. Moreover, in 45o wave heading (quartering sea) it demonstrates a slightly lower disparity compared to the 0o wave heading (following sea) through sea-state 1-4 standing for 50%, 37%, 24% and 16% respectively.
Open Access
A symmetric experimental study of the interaction between regular waves and a pontoon breakwater with novel fin attachments
(MDPI, 2024-12-02) Lyu, Xiangcheng; Yang, Yifeng; Mi, Chenhao; Tang, Chi Man; Adeboye, Lukman; Farhan, Mohamed; Collins, Stan; Ou, Binjian; Wong, Anson; Duffy, John Gordon; Huang, Luofeng
Floating breakwaters are widely applied on the ocean water surface to protect human infrastructure from the destructive power of waves. This study designs and investigates the performance of a novel symmetric-pontoon floating breakwater with a symmetric pair of hydrofoils. Based at the Cranfield Ocean Systems Laboratory, the system was constructed and tested in various wave conditions using different fin configurations. The floating structure was anchored using a symmetric four-point mooring system. The tested waves were regular and symmetric perpendicular to the propagating direction. Key parameters, including the attenuated wave amplitude, motions of the breakwater, and the mooring forces, were measured. The wave parameters utilised for testing covered 1.61–5.42 relative wavelength to structural length, with wave heights of 3 cm and 5 cm. Results showed the 90° fin configuration can reduce wave transmission by up to 74%, with the lowest mooring forces at 3.05 relative wavelength, enhancing the performance of wave energy dissipation and structural seakeeping. At 90° setup, the mooring force was lowest at 2.41 relative wavelength. This research can inform novel designs of breakwaters to improve protection abilities for coastal cities and offshore infrastructures, especially renewable energy systems.
Open Access
An interdisciplinary literature review of floating solar power plants
(Elsevier, 2025-03) Wei, Yujia; Khojasteh, Danial; Windt, Christian; Huang, Luofeng
Floating photovoltaic is predicted to be the most ubiquitous energy technology in the future, with global installations projected to reach 10 GW by 2030, potentially generating 13.5 TWh of clean electricity annually. The extrapolation of solar power plants from land-based to water-based requires interdisciplinary expertise from fields such as energy systems, hydrodynamics, structures, environments, and electrical engineering. To bridge the disciplines, the present review analyses existing floating solar related publications comprehensively. Initially, a comprehensive literature scan of over 900 publications is presented, selectively leading to approximately 400 papers included. Subsequently, three review sectors are presented: design, modelling, and environmental effects. These cover various structural components, system-air-water interactions, their modelling approaches, power output prediction, and potential impacts on the surrounding environment including vegetation and animals. Key findings suggest the potential for enhancing energy efficiency through water-based cooling techniques, innovative modularised designs to support upscaling, positive environmental impacts including artificial habitats, and the utilisation of advanced marine structure designs such as a breakwater to protect the solar systems from ocean wave loads. In addition, the levelised cost of electricity of various floating solar studies are presented, including both theoretical and practical projects. The levelised cost of electricity has been decreasing, to a level of 0.05–0.07 USD/kWh, making FPV increasingly competitive as a clean and affordable energy choice. Overall, this review aims to facillitate interdisciplinary research and projects on the booming floating photovoltaic industry.
Open Access
Array analysis on a seawall type of deformable wave energy converters
(Elsevier, 2024-03-24) Wei, Yujia; Wang, Chao; Chen, Wenchuang; Huang, Luofeng
There has been a significant interest in developing Flexible Wave Energy Converters (FlexWECs) that utilise structural deformations to generate electricity and mitigate destructive wave loads to the devices. In the meantime, FlexWECs are most likely to operate in an array format to enhance space usage and power output, as well as provide convenience for maintenance. In this context, the present paper develops a high-fidelity computational model to investigate the interaction of ocean surface waves with an array of seawall-type FlexWECs, which can meanwhile serve coastal engineering purposes. The fluid field is solved using the Navier-Stokes equations, and structural deformations are predicted using a nonlinear finite-element method. Hydroelastic interactions of up to seven deforming FlexWECs with the surrounding wave fields are demonstrated through systematic simulation cases. Based on the simulation results, analyses are conducted to investigate how the wave farm energy output is influenced by the gap between individual devices and the number of devices deployed. Accordingly, empirical design suggestions are provided. Overall, this work innovatively simulates the hydroelastic interactions between waves and multiple deforming structures, and the provided insights are useful for promoting the development of FlexWECs and their wave farms.
Open Access
A combined experimental and numerical approach to predict ship resistance and power demand in broken ice
(Elsevier, 2023-12-11) Xue, Yanzhuo; Zhong, Kai; Ni, Bao-Yu; Li, Zhiyuan; Bergstrom, Martin; Ringsberg, Jonas W.; Huang, Luofeng
Despite its remoteness and hostile environmental conditions, the Arctic holds significant shipping lanes, such as the Northern Sea Route (NSR) and the Northwest Passage (NWP). Typically, merchant ships operate along these routes in summer only, when the dominating type of ice is broken ice. A challenge of operating in such ice conditions is that there is no cost- and time-efficient method for predicting the resulting ice resistance, which makes route planning difficult, among others. To address this challenge, we present and analyze two complementary approaches to predict ship resistance in broken ice, of which one is experimental and the other numerical. The experimental approach makes use of a type of non-refrigerated synthetic model ice made of polypropylene, which makes it possible to test how a ship behaves in broken ice using a conventional non-refrigerated towing tank rather than an ice tank. The numerical approach, in turn, is based on the CFD-DEM method and can be used to consider fluid effects, such as the changes in fluid velocity and ship waves, while the ship is moving ahead. Validation calculations against established empirical approaches indicate that both approaches are reasonably accurate.
Open Access
Compression after impact behavior of asymmetrically tapered laminates: experimental and numerical studies
(Elsevier, 2024-12-01) Yu, Xiaonan; Xu, Xiwu; Huang, Luofeng; Qin, Qing; Zhang, Chao
This paper presents experimental and numerical studies on the compression after impact (CAI) behavior of composite tapered laminates. It introduces newly designed impact platforms and compression fixtures specifically tailored for the specimens. Drop-weight impacts are applied to the center of the specimens, and the resulting damage is briefly described. Compression tests are then conducted on both non-impacted and impacted specimens, with strain gauges used to monitor the strain distribution. Internal damage is detected using CT scanning and ultrasonic C-scan techniques. The numerical simulations are performed using ABAQUS/Explicit finite element analysis (FEA), incorporating an intra-laminar progressive damage model and an inter-laminar cohesive model, while additionally modeling resin pockets as elastomers. The simulation and experimental results indicate that before compression failure, impact damage in the thin section minimally affects the out-of-plane displacement, which is predominantly influenced by structural asymmetry. Stress concentration is observed at the junction between the thin and tapered sections in the compression test, while in the CAI test, stress concentration appears in the impact zone. The impact induces a notable shift in failure location and damage modes, resulting in decreased compressive strength, although the impact on stiffness remains minimal.
Open Access
Cost-benefit analysis of a trans-Arctic alternative route to the Suez Canal: a method based on high-fidelity ship performance, weather, and ice forecast models
(MDPI, 2023-03-25) Li, Zhiyuan; Ding, Li; Huang, Luofeng; Ringsberg, Jonas W.; Gong, Hui; Fournier, Nicolas; Chuang, Zhenju
Climate change in recent years has produced viable shipping routes in the Arctic. However, critical uncertainties related to maritime operations in the Arctic make it difficult to predict ship speeds in ice and, thus, the voyage time and fuel costs. Cost–benefit analysis of alternative Arctic routes based on accurate environmental condition modeling is required. In this context, this paper presents a holistic approach that considers the major voyage-related costs of a trans-Arctic route as an alternative to the conventional routes via the Suez Canal Route (SCR) for existing merchant ships. This tool is based on high-fidelity models of ship performance, metocean forecasting, and a voyage optimization algorithm. Case studies are performed based on a general cargo vessel in operation to quantify realistic expenses inclusive of all the major operational, fuel, and voyage costs of the specific voyages. A comparison is made between the total costs of the trans-Arctic route and SCR for different seasons, which proves the economic feasibility of the trans-Arctic route. Overall, this work can provide valuable insights to help policymakers as well as shipbuilders, owners, and operators to assess the potential cost-effectiveness and sustainability of future Arctic shipping, thereby better developing future strategies.
Open Access
Coupled analysis between catenary mooring and VLFS with structural hydroelasticity in waves
(Elsevier, 2023-09-12) Wei, Yujia; Yu, Shuangrui; Jin, Peng; Huang, Luofeng; Elsherbiny, Khaled; Tezdogan, Tahsin
The rapid growth of marine renewables has led to the development of very large floating structures (VLFS) that are designed to operate in deep seas. It is significant to understand the mechanism of the coupled effects between deformable VLFS and catenary mooring system. This paper presents a time-domain hydro-elastic-moored model developed by integrating a quasi-static mooring module into a fully coupled Computational Fluid Dynamics (CFD) - discrete-module-beam (DMB) approach. The model is used to investigate the coupled effects between structural hydroelasticity and loose-type mooring systems on a deformable VLFS in waves. The mooring and hydroelasticity codes are validated separately and show favourable agreement with other numerical and experimental results. Then the coupled effects between the mooring system and structural hydroelasticity are evaluated by assigning various design parameters, i.e., VLFS structural stiffness and mooring stiffness. The numerical results, including dynamic motions, longitudinal vertical bending moments (VBMs) and mooring tension forces are presented and analysed. These results can be used to design a VLFS with mooring in medium-deep sea, and help with the conventional mooring design for a less-stiffness VLFS due to hydroelastic response.
Open Access
COVID-19 transmission inside a small passenger vessel: risks and mitigation
(Elsevier, 2022-05-19) Huang, Luofeng; Riyadi, Soegeng; Utama, I.K.A.P.; Li, Minghao; Sun, Peiyign; Thomas, Giles
The global shipping industry has been severely influenced by the COVID-19 pandemic; in particular, a significant amount of passenger transportation has been suspended due to the concern of COVID-19 outbreak, as such voyages confine a dense crowd in a compact space. In order to accelerate the recovery of the maritime business and minimise passengers' risk of being infected, this work has developed a computational model to study the airborne transmission of COVID-19 viruses in the superstructure of a full-scale passenger vessel. Considering the vessel advancing in open water, simulations were conducted to study the particulate flow due to an infected person coughing and speaking, with the forward door open and closed. The results suggest that keeping the forward door closed will help prevent the external wind flow spreading the virus. When the forward door is closed, virus particles' coverage is shown to be limited to a radius of half a metre, less than a seat's width. Thus, an alternate seat arrangement is suggested. Furthermore, investigations were conducted on the influence of wall-mounted Air Conditioner (AC) on the virus transmission, and it was found that controlling the AC outlet direction at less than 15° downward can effectively limit the virus spread. Meanwhile, it was demonstrated that an AC's backflow tends to gather virus particles in a nearby area, thus sitting farther from an opening AC may reduce the risk of being infected. Overall, this work is expected to inform hygienic guidelines for operators to counter COVID-19 and potentially similar viruses in the future.
Open Access
Developing reliable floating solar systems on seas: a review
(Elsevier, 2025-04-01) Huang, Luofeng; Elzaabalawy, Hashim; Sarhaan, Mohamed; Sherif, Ahmed; Ding, Haoyu; Ou, Binjian; Yang, Danlei; Cerik, Burak Can
Solar PhotoVoltaic (PV), as a clean and affordable energy solution, has become ubiquitous around the world. In order to install enough PV coverage to meet the demand of global climate action, there has been a growing research interest in deploying solar panels on abundant sea space. However, the harsh marine environment is holding stakeholders back with safety concerns. There is a necessity to ensure the reliability of FPV on seas. To facilitate research in this area, the present review scans all Floating PV (FPV) literature related to the ocean, with a focus on reliability and risk mitigation. It starts by presenting contemporary and potentially future FPV designs for seas, inventorying both mechanical and electrical components. Accordingly, possible risks in the system are discussed with the associate mitigations suggested. Subsequently, a series of protective approaches to assess offshore wind and wave loads on FPV are introduced. This is followed by a structural integrity review for the system’s fatigue and ultimate strength, accompanied by anti-corrosion, anti-biofouling, and robust mooring concerns. Finally, essential research gaps are identified, including the modelling of numerous floating bodies on seas, mooring methodology for enormous FPV coverage, the interactions between FPV and the surrounding sea environments, and remote sensing and digital twins of the system for optimal energy efficiency and structural health. Overall, this work provides comprehensive insights into essential considerations of FPV on seas, supporting sustainable developments and long-term cost reductions in this sector.
Open Access
Effects of a breakwater on a floating solar farm in heading and oblique waves
(AIP Publishing, 2024-11-01) Zou, Detai; Wei, Yujia; Ou, Binjian; Zhang, Chao; Chu, Shengnan; Huang, Luofeng
Floating photovoltaic (FPV) solar farms have gained significant research and industrial interest in recent years. However, to support its deployment in abundant ocean space, FPV is required to be protected against wave loading. Thus, the usage of a breakwater in front of a floating solar farm is particularly promising. In this work, a time-domain simulation model for an array of FPV solar units in heading and oblique waves was established. Following validation against experiments, the model was used to predict the wave-induced motion and loading responses of each floating solar unit in an array, first without a breakwater, and subsequently with a breakwater. By comparison, it was found that a breakwater can reduce the wave-induced motions of a floating solar farm by up to 56%, alongside up to 55% reduction of loading on the joints between FPV units. However, the breakwater is less effective in relatively long waves and could induce some increase in loading on joints, signifying future work to optimize the design of the breakwater based on the intended environmental condition. Overall, the present results provide insights into a practical breakwater solution for FPV in offshore and coastal conditions, supporting the long-term development of this industry.
Open Access
Energy efficiency analysis of a deformable wave energy converter using fully coupled dynamic simulations
(MDPI, 2024-04-15) Luo, Chen; Huang, Luofeng
Deformable wave energy converters have significant potential for application as flexible material that can mitigate structural issues, while how to design the dimensions and choose an optimal deployment location remain unclear. In this paper, fully coupled computational fluid dynamics and computational solid mechanics were used to simulate the dynamic interactions between ocean waves and a deformable wave energy converter. The simulation results showed that the relative length to wave, deployment depth and aspect ratio of the device have significant effects on the energy conversion efficiency. By calculating the energy captured per unit width of the device, the energy efficiency was found to be up to 138%. The optimal energy conversion efficiencies were achieved when the structure length was 0.25, 0.5 or 0.75 of the dominating wavelength and submerged at a corresponding suitable depth. The aspect ratio and maximum stress inside the wave energy converter showed a nonlinear trend, with potential optimal points revealed. The simulation approach and results support the future design and optimisation of flexiable wave energy converters or other marine structures with notable deformations.
Open Access
Energy fluctuation of floating photovoltaic solar panel due to wave-induced motions
(American Society of Mechanical Engineers, 2024-06-09) Huang, Luofeng
Solar photovoltaic is predicted to be the most widely used energy method in the future. However, the expansion of solar panels is currently limited by scarce land and lake spaces. To meet the world’s future clean energy target, floating solar panels are expected to be deployed on abundant ocean space, but floating solar panels on the ocean will be subject to loads and motions induced by waves. In particular, a continuous rotation can cause the solar panel surface to constantly change its sunlight intake angle, which could lead to a loss of energy. To investigate this phenomenon, a novel interdisciplinary experimental facility has been established, where a solar simulator was installed on top of a wave tank. A floating solar unit is placed in high-concentration light beams and subject to wave-induced motions. Its motions are measured and related to the power output. It was found that the average power output oscillates due to the motions, and an evident power loss was shown by the rotational motion. For all the tested wave conditions, the highest pitch amplitude of 6.7° corresponds to a significant level of 12.7% average power loss. Overall, the work presents a novel experimental approach and results that can estimate power output for floating solar projects in wave environments. The results also highlight the importance of considering wave attenuation technologies to avoid direct wave interaction with floating solar units.
Open Access
Enhanced data-driven economic assessment of fuel cell electric buses utilizing an improved Markov chain Monte Carlo approach
(Elsevier, 2025-02-10) Yuan, Xinjie; Xu, Miao; Hou, Zhongjun; Chen, Wenchuang; Huang, Yun; Lv, Jiaming; Xu, Xudong; Huang, Luofeng
Accurate economic assessment of proton exchange membrane fuel cell (PEMFC) vehicles is essential for optimizing control strategies in the PEMFC industry, which is largely driven by the need to reduce costs. Traditional data-driven approaches have focused on reconstructing typical driving cycles from real-world speed data, often overlooking the intensity and acceleration of these cycles. These factors are crucial for water and heat management in PEMFCs and can lead to inaccurate estimates of hydrogen consumption. This paper introduces a novel algorithm for typical driving cycles reconstruction based on real-world data, named the improved two-dimensional Markov Chain Monte Carlo (2D MCMC) approach using Metropolis-Hastings (M − H) sampling. The approach innovatively encodes the integration of real-time vehicle speed and acceleration sequences into a hierarchical 2D state transition probability matrix. To optimise both accuracy and computation time, the M − H based sampler is newly introduced to generate typical driving cycle without the computational burden of multiplying large matrices. Moreover, by integrating the agglomerative nesting (AGNES) alongside a comprehensive evaluation system that incorporates simulation and bench testing, the proposed approach effectively weights real-world route conditions in the economic assessment. Case studies involving 10 PEMFC hybrid buses in Shanghai, China, validate the effectiveness and robustness of the proposed method. Comparative analyses show that the relative errors in hydrogen consumption per 100 km between the reconstructed and real-world driving cycles are within 1.20–3.01% for all ten buses in Shanghai, with computation times reduced by up to 12.60% compared to the existing methods.
Open Access
Floating PV systems as an alternative power source: case study on three representative islands of Indonesia
(MDPI, 2024-02-05) Esparza, Ignacio; Olábarri Candela, Ángela; Huang, Luofeng; Yang, Yifeng; Budiono, Chayun; Riyadi, Soegeng; Hetharia, Wolter; Hantoro, Ridho; Setyawan, Dony; Utama, I. K. A. P.; Wood, Tim; Luo, Zhenhua
Floating solar renewable energy is of enormous potential in Indonesia. This paper presents a comprehensive study of the design of Floating Photovoltaic (FPV) systems with Battery Energy Storage Systems (BESS) for three islands in Indonesia. These islands represent three typical scenarios in Indonesia (a) using a national grid powered by fossil fuel generators, (b) using a local grid powered by diesel generators, and (c) no grid at all. In-person surveys were conducted at these islands to collect data, and then FPV and BESS were designed to meet the demands of each island. Subsequently, the systems’ energy simulations were conducted using the System Advisor Model, demonstrating daily energy demand and supply in hour variation. Based on the results, a series of sustainability analyses were created from the aspects of economics, society, and the environment. The economic analysis demonstrated cost savings by using FPV to replace contemporary energy methods. The social analysis provides valuable insights into the local community, forming a demographic profile and obtaining perceptions and opinions regarding the new energy approach. The environmental analysis quantifies the potential CO2 emissions. Overall, the work provides valuable insights into the roadmap for implementing floating solar technologies in Indonesia which can also inform global ocean-based solar energy developments.
Open Access
Floating solar power loss due to motions induced by ocean waves: an experimental study
(Elsevier, 2024-11-15) Huang, Luofeng; Yang, Yifeng; Khojasteh, Danial; Ou, Binjian; Luo, Zhenhua
Whilst there is an interest in floating solar energy systems in coastal and offshore regions to utilise available sea space, they are subject to ocean waves that introduce constant momentum. Consequently, solar panels undergo periodic motions with the waves, causing a continuous change in tilt angle. The tilt angle variation is a sub-optimal process and leads to a loss of energy harnessing efficiency. To investigate this phenomenon, the present study innovatively installed a solar simulator on top of a wave tank. The solar simulator was used to generate high-strength light beams, under which, a floating solar unit was subject to periodic incident waves. Wave-induced motions to the solar system as well as the output power were measured. A systematic analysis of the results indicated that a floating solar unit can have significantly lower power output in waves, compared to its calm-water counterpart. An evident link was established between the wave-induced power loss and the wave-induced rotational movement of the panel. An empirical equation was derived which shows the power loss is predictable through the rotational amplitude. The results also highlight the importance of implementing wave attenuation technologies such as breakwaters to minimise wave-induced motions to floating solar systems. Overall, this research presents a novel experimental approach to assess the difference of floating solar power in ocean-wave versus calm-water scenarios, providing valuable insights for future solar projects on the ocean.
Open Access
Fully-coupled hydroelastic modeling of a deformable wall in waves
(Elsevier, 2022-11-16) Hu, Zhengyu; Huang, Luofeng; Li, Yuzhu
The hydroelastic behavior of a vertical wall in periodic waves is investigated using a fully-coupled computational fluid dynamics (CFD) and computational solid mechanics (CSM) model. The present numerical model is verified against previous numerical and experimental results on wave evolution and structural displacement. Then the hydrodynamic characteristics and the structural responses of an elastic wall in periodic waves are parametrically investigated. It is demonstrated that wave reflection, run-up, and loading decrease as the wall becomes more flexible. The decreases also occur when the waves become shorter. With nonlinear wave propagation, both the displacement and the stress of the wall are larger in the shoreward direction than those in the seaward direction. The wall displacement has the same frequency as the exciting waves and the stress increases with the decrease of the ratio of the wave frequency to the wall’s natural frequency. Considering the effect of flexibility, empirical formulae are proposed for predicting the wave run-up, loading, and maximum displacement of the wall. Besides, the optimization of the flexible wall is conducted by taking into account both the defense performance (i.e., transmission coefficient) and the structural integrity (i.e., maximum von Mises stress). Finally, the effect of the material damping is studied, which shows that the material damping has a negligible effect on the interaction between periodic waves and the elastic structure.
Open Access
Hydrodynamic analysis of a heave-hinge wave energy converter combined with a floating breakwater
(Elsevier, 2024-01-02) Wei, Yujia; Yu, Shuangrui; Li, Xiang; Zhang, Chongwei; Ning, Dezhi; Huang, Luofeng
Research interest in breakwater design has increased recently due to the impetus to develop marine renewable energy systems, as breakwaters can be retrofitted to harness wave energy at the same time as attenuating it. This study investigates a novel system of attaching a hinge baffle under a floating breakwater. The floating breakwater itself acts as a heaving wave energy converter, and meanwhile the hinge rotation provides a second mechanism for wave energy harnessing. A computational model with multi-body dynamics was established to study this system, and a series of simulations were conducted in various wave conditions. Both wave attenuation performance and energy conversion ratio were studied, using an interdisciplinary approach considering both coastal engineering and renewable energy. In particular, the performance of the proposed system is compared with contemporary floating breakwater designs to demonstrate its advantage. Overall, a useful simulation framework with multi-body dynamics is presented and the simulation results provide valuable insights into the design of combined wave energy and breakwater systems.