Applied Ocean Research最新文献

{"title":"Estimating cross-shore and longshore sediment transport from shoreline observation data","authors":"Changbin Lim ,&nbsp;Mauricio González ,&nbsp;Jung-Lyul Lee","doi":"10.1016/j.apor.2024.104288","DOIUrl":"10.1016/j.apor.2024.104288","url":null,"abstract":"<div><div>To effectively address beach morphology, it is crucial to not only analyze shoreline characteristics but also understand sediment transport influenced by wave dynamics and storm-induced sediment behavior. Shoreline changes occur over long-term, mid-term, and short-term periods, each impacting beach morphology differently. Therefore, investigating sediment transport under wave action is essential for accurately identifying beach morphology causes. However, existing studies have been deficient in this regard. We propose a method to estimate cross-shore and longshore sediment components of coastal sediment transport and suspended sediment concentration from observed shoreline data, based on the sediment volume conservation rule. The study focuses on shoreline data observed at Jeongdongjin, Korea. The outcome of this research is expected to significantly contribute to coastal management. This is achieved by indirectly determining these sediment components from shoreline observation data, providing valuable insights for coastal management strategies.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104288"},"PeriodicalIF":4.3,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrodynamic performance study of floating photovoltaic arrays with multiple floating bodies","authors":"Wanhai Xu,&nbsp;Yumeng Sun,&nbsp;Ziqi He","doi":"10.1016/j.apor.2024.104286","DOIUrl":"10.1016/j.apor.2024.104286","url":null,"abstract":"<div><div>In the context of the global transition to renewable energy, floating photovoltaic systems have garnered significant attention as an innovative method of energy utilization. To investigate the impact of different arrangements of floating photovoltaic (FPV) systems on hydrodynamic performance, fully coupled numerical simulations of wind, wave and current were conducted in ANSYS-AQWA for three arrangements: rectangular array, linear array, and honeycomb-like array. The analysis focused on the six degrees of freedom motions and maximum mooring force under operational and survival conditions. It can be found that the rectangular array exhibits the strongest system stability, effectively reducing the mooring force and showing insensitivity to variations in load incident angles. These findings provide a theoretical foundation and engineering guidance for the design of FPV systems, offering substantial practical application value.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104286"},"PeriodicalIF":4.3,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting coastal wave conditions: A simple machine learning approach","authors":"Edward Roome,&nbsp;David Christie,&nbsp;Simon Neill","doi":"10.1016/j.apor.2024.104282","DOIUrl":"10.1016/j.apor.2024.104282","url":null,"abstract":"<div><div>Accurate and reliable nearshore wave predictions are highly valuable for a range of marine activities, including coastal engineering and maritime transport. However, in nearshore locations, predicting wave properties is challenging due to complex shallow water processes, requiring local wave models. This article develops an alternative data-driven framework to predict wave parameters (e.g. significant wave height) through the extension of wave buoy datasets using a trained Gaussian process regression (GPR — a supervised machine learning method). We present an easy-to-implement workflow, where the extensive range of input parameters (from ECMWF’s (1) ERA5 reanalysis and (2) IFS forecast global wave model, <span><math><mrow><mo>≈</mo><mn>50</mn><mspace></mspace><mi>km</mi></mrow></math></span> resolution) drives the development of GPR models. At five contrasting locations around the United Kingdom’s coastline, the GPR models produce wave predictions (forecast and hindcast) with low bias scores and strong correlations with observations. When compared to the <em>global</em> (ERA5 reanalysis) and a benchmark <em>shelf-scale</em> (Atlantic-European North West Shelf reanalysis; AENWS, <span><math><mrow><mn>1</mn><mo>.</mo><mn>5</mn><mo>−</mo><mn>3</mn><mo>.</mo><mn>0</mn><mspace></mspace><mi>km</mi></mrow></math></span> resolution) model, the GPR hindcasts reduced significant wave height (<span><math><msub><mrow><mi>H</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span>) root-mean-squared error (RMSE) from 0.46 m (ERA5) and 0.21 m (AENWS) to 0.16 m (GPR). For the average zero-crossing wave period (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>z</mi></mrow></msub></math></span>) RMSE reduced from 1.46 s (ERA5) and 1.15 s (AENWS) to 0.58 s (GPR). Because our approach uses publicly available global data, it can be implemented at any historic or active buoy location. We provide proof of concept for an online forecast and hindcast tool which has the potential to improve accessibility to coastal wave predictions for many marine stakeholders.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104282"},"PeriodicalIF":4.3,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on the damage characteristics of steel fiber reinforced concrete slabs attacked by chloride ion under contact explosion","authors":"Xiaohua Zhao ,&nbsp;Guo Jiang ,&nbsp;Lin Yang ,&nbsp;Yongsheng Jia ,&nbsp;Hongyuan Fang ,&nbsp;Jinshan Sun ,&nbsp;Haonan Zhao","doi":"10.1016/j.apor.2024.104270","DOIUrl":"10.1016/j.apor.2024.104270","url":null,"abstract":"<div><div>In order to study the damage characteristics of steel fiber reinforced concrete slabs attacked by chloride ion under explosive loading, contact explosion tests were performed for nine pieces of 500 mm × 500 mm × 60 mm slabs. These slabs were divided into three groups based on corrosion time of seawater (uncorroded, corrosion for 10 days, corrosion for 20 days) to achieve different degrees of chloride ion erosion effect. The dynamic response of the steel fiber reinforced concrete slab under contact blast loading were compared and analyzed, and the effects of explosives quality and degree of corrosion were explored. Besides, the propagation characteristics of the stress wave in the slab and the typical damage mode were also studied. The results show that the damage degree of steel fiber reinforced concrete slab has a non-linear increase with the increase of seawater corrosion. Slabs suffer different damage patterns such as cratering and spalling for different qualities of explosives. In addition, based on the experimental results, an empirical formula for predicting the diameter of the blast crater was established.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104270"},"PeriodicalIF":4.3,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrodynamic performance comparison of planing catamarans with mono-hulls using numerical and experimental methods","authors":"Milad Shajaripour,&nbsp;Hamid Zeraatgar","doi":"10.1016/j.apor.2024.104283","DOIUrl":"10.1016/j.apor.2024.104283","url":null,"abstract":"<div><div>This study addresses the hydrodynamic performance of high-speed planing catamarans compared to equivalent mono-hulls using numerical simulations and experimental validation. The study includes computational fluid dynamics (CFD) simulations to analyse the hydrodynamic behaviour of the catamarans under various operating conditions, such as different speeds, deadrise angles, and static trim angles. Comparison of the numerical simulation results with model tests reveals that the numerical results for the resistance of planing catamarans at high speeds deviate significantly from the experimental data due to strong spray. This discrepancy is systematic (rather than random) and has been recognised and modified. The modified numerical results are sufficiently accurate for further pursuit. Generally, the resistance of a planing catamaran compared to an equivalent planing mono-hull is significantly larger, approximately 25–60 %, while the absolute sinkage is lower. A positive feature of the catamaran is its ability to prevent porpoising instability, especially in boats with a small deadrise angle. Choosing a planing catamaran over a mono-hull must offer other substantial advantages, such as better seakeeping performance, which compensate the higher resistance.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104283"},"PeriodicalIF":4.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fuzzy-based ensemble methodology for accurate long-term prediction and interpretation of extreme significant wave height events","authors":"C. Peláez-Rodríguez ,&nbsp;J. Pérez-Aracil ,&nbsp;A.M. Gómez-Orellana ,&nbsp;D. Guijo-Rubio ,&nbsp;V.M. Vargas ,&nbsp;P.A. Gutiérrez ,&nbsp;C. Hervás-Martínez ,&nbsp;S. Salcedo-Sanz","doi":"10.1016/j.apor.2024.104273","DOIUrl":"10.1016/j.apor.2024.104273","url":null,"abstract":"<div><div>Providing an accurate prediction of Significant Wave Height (SWH), and specially of extreme SWH events, is crucial for coastal engineering activities and holds major implications in several sectors as offshore renewable energy. With the aim of overcoming the challenge of skewness and imbalance associated with the prediction of these extreme SWH events, a fuzzy-based cascade ensemble of regression models is proposed. This methodology allows to remarkably improve the predictive performance on the extreme SWH values, by using different models specialised in different ranges on the target domain. The method’s explainability is enhanced by analysing the contribution of each model, aiding in identifying those predictor variables more characteristic for the detection of extreme SWH events. The methodology has been validated tackling a long-term SWH prediction problem, considering two case studies over the southwest coast of the United States of America. Both reanalysis data, providing information on various meteorological factors, and SWH measurements, obtained from the nearby stations and the station under examination, have been considered. The goodness of the proposed approach has been validated by comparing its performance against several machine learning and deep learning regression techniques, leading to the conclusion that fuzzy ensemble models perform much better in the prediction of extreme events, at the cost of a slight deterioration in the rest of the samples. The study contributes to advancing the SWH prediction field, specially, to understanding the behaviour behind extreme SWH events, critical for various sectors reliant on oceanic conditions.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104273"},"PeriodicalIF":4.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the value of Fano resonance in wave energy converters","authors":"Andrei M. Ermakov ,&nbsp;Jack L. Rose-Butcher ,&nbsp;John V. Ringwood","doi":"10.1016/j.apor.2024.104276","DOIUrl":"10.1016/j.apor.2024.104276","url":null,"abstract":"<div><div>The article evaluates the potential of the Fano resonance operational principle in wave energy converters (WECs), using a 2-body loosely moored self-referenced WEC as an illustrative example. By leveraging Fano resonance, the point absorber buoy can remain relatively stationary with low loading on mooring lines, serving as an efficient wave energy transmitter while concurrently achieving resonance within the internal power take-off (PTO) system. This arrangement reduces the motion of the point absorber hull, thereby decreasing loads on the WEC structure, mooring lines, and anchors. As a result, operational and structural costs are minimised, further reducing the levelised costs of generated energy. Additionally, by ensuring minimal fluctuations in the WEC, confidence in using traditional linear mathematical models is increased, as commonly employed for WEC performance assessment and control design.</div><div>The article presents a resonance study and introduces newly derived solutions in the frequency domain for the proposed operational concept. It analytically demonstrates the viability of employing the Fano resonance operational strategy for WECs, suggesting that this strategy has the potential to compete with traditional methods of wave energy transformation. Furthermore, the insights gained from the study contribute to identifying optimal parameters for a PTO system, as well as optimising the design of the heaving buoy.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104276"},"PeriodicalIF":4.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Directional enhancement of underwater impact and bubble loads in neighbor two-phase fluid domains charge","authors":"Yifan Dong ,&nbsp;Wei Han ,&nbsp;Rennian Li ,&nbsp;Haozhi Nan ,&nbsp;Xiaobo Shen ,&nbsp;Shiqi Yang ,&nbsp;Lu Bai","doi":"10.1016/j.apor.2024.104269","DOIUrl":"10.1016/j.apor.2024.104269","url":null,"abstract":"<div><div>The loading characteristics of underwater explosions and the dynamic behavior of bubbles are directly related to the charge structure. This study proposes a unique charge structure in a gas–liquid two-phase fluid domain. Numerical methods are used to investigate the effects of fluid layer thickness and gas–liquid ratio on underwater explosion shock wave load, bubble dynamics, and bubble pulsation load. The results show that the two-phase fluid layer significantly enhances the directional release of shock wave energy and bubble pulsation load. During the shock wave phase, a lagging wave effect appears in the liquid layer direction, causing a secondary high-energy shock, significantly increasing the specific impulse. The gas layer direction may form a pressure relief channel effect, enhancing the shock wave peak pressure. For the bubble motion phase, differences in the physical properties of the fluid layer medium lead to irregular bubble boundary movements, promoting bubble tearing and rupture. The gaseous medium converts the accumulated shock wave energy into the internal energy of the bubble, increasing its volume potential. Although this characteristic reduces the pulsation frequency, it significantly increases the specific impulse. Altering the fluid layer medium can control explosion loads and bubble movement, offering new insights for ocean engineering applications.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104269"},"PeriodicalIF":4.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of scour depth around monopiles in combined waves and current: A probabilistic assessment of M5’-MCS","authors":"Tongshun Yu ,&nbsp;Xin Tong ,&nbsp;Xuguang Chen ,&nbsp;Haoyang Song ,&nbsp;Xuewen Zhao ,&nbsp;Yuqiao Wang","doi":"10.1016/j.apor.2024.104271","DOIUrl":"10.1016/j.apor.2024.104271","url":null,"abstract":"<div><div>Addressing the overlooked uncertainties and stochastic elements in prior studies on scour prediction, this research introduces a probabilistic prediction model for the scour depth around monopile foundations. To enhance the accuracy of the model, the M5’ model tree method was employed to construct a deterministic prediction formula, which was then evaluated using statistical indicators for performance. To address the issue of discontinuities within the deterministic formula, a continuity treatment was applied to improve the credibility of the formula. Expanding on the deterministic formula, a probabilistic model for estimating the local scour depth around a monopile subjected to combined wave and current conditions was developed using Monte Carlo simulations. These simulations integrated specific random parameters into the deterministic model, allowing for the assessment of how these parameters influence the failure probability. The results indicate that the M5’ model tree algorithm can effectively predict the equilibrium scour depth of a monopile under the influence of waves and currents, and the formula, post-continuity treatment, demonstrates enhanced credibility and applicability. Furthermore, the study indicates that the failure probability of a monopile escalates in relation to the increase in near-bed current velocity and the rise in maximum bed surface orbital velocity. It was also discovered that within a specific Froude number range, a consistently low failure probability is maintained, a conclusion that provides a reference for the design of monopile foundations.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104271"},"PeriodicalIF":4.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of axial launch spacing on cavitation interference and load characteristics during underwater salvo","authors":"Shan Gao ,&nbsp;Yao Shi ,&nbsp;Pengcheng Ye ,&nbsp;Shuai Zhang ,&nbsp;Guang Pan","doi":"10.1016/j.apor.2024.104281","DOIUrl":"10.1016/j.apor.2024.104281","url":null,"abstract":"<div><div>This paper analyzes the effect of launch interval on cavitation flow interference and load characteristics during underwater salvo. The study employs the Improved Delayed Detached Eddy Simulation and the Schnerr-Sauer cavitation model, Volume of Fluid (VOF) multiphase flow model, and overlapping grid. Additionally, decompression experiment systems are designed, and numerical simulations are found to be in good agreement with experimental results, thus verifying the effectiveness of the simulation. Detailed discussions are provided on multiphase flow field and load distribution. The results reveal a top-down collapse process of the cavity, with collapse shrinking to an isolated bubble at the end. Synchronized collapse pressure is characterized by short pulse widths at the peaks, all located at the lowermost part of the cavity. During the underwater stage, when the axial launch spacing ranges between 0.5 times and 1.0 times the length of the projectile, the head of the second projectile acts on the area below the center of mass of the first. This leads to gradual stabilization of the initial cavity and a decrease in deviation of the center of mass toward the inside. Despite experiencing large-scale fracture and detachment due to interference from the wake of the first engine, the motion stability of the inside cavity of the second projectile remains intact. In the water exit stage, when the axial launch spacing ranges between 0.75 times and 1 time the length of the projectile, it causes expansion and contraction of the inside cavity of the second projectile. However, asymmetric synchronous collapse loads may occur, leading to unstable motion posture.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":"153 ","pages":"Article 104281"},"PeriodicalIF":4.3,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}