Showing papers on "Wave height published in 2023"
TL;DR: In this paper , the authors used metaheuristic optimization methods to investigate the effects of geometric factors on the performance of an Oscillating Surge Wave Energy Converter (OSWEC), in addition to the effect of hydrodynamic parameters.
Abstract: In recent years, there has been an increasing interest in renewable energies in view of the fact that fossil fuels are the leading cause of catastrophic environmental consequences. Ocean wave energy is a renewable energy source that is particularly prevalent in coastal areas. Since many countries have tremendous potential to extract this type of energy, a number of researchers have sought to determine certain effective factors on wave converters’ performance, with a primary emphasis on ambient factors. In this study, we used metaheuristic optimization methods to investigate the effects of geometric factors on the performance of an Oscillating Surge Wave Energy Converter (OSWEC), in addition to the effects of hydrodynamic parameters. To do so, we used CATIA software to model different geometries which were then inserted into a numerical model developed in Flow3D software. A Ribed-surface design of the converter’s flap is also introduced in this study to maximize wave-converter interaction. Besides, a Bi-level Hill Climbing Multi-Verse Optimization (HCMVO) method was also developed for this application. The results showed that the converter performs better with greater wave heights, flap freeboard heights, and shorter wave periods. Additionally, the added ribs led to more wave-converter interaction and better performance, while the distance between the flap and flume bed negatively impacted the performance. Finally, tracking the changes in the five-dimensional objective function revealed the optimum value for each parameter in all scenarios. This is achieved by the newly developed optimization algorithm, which is much faster than other existing cutting-edge metaheuristic approaches.
3 citations
TL;DR: In this paper , the wave model WAVEWATCHIII is used to produce wave information, until the end of the 21st century, covering all ocean areas, and the period is divided into four 30-year slices, where the first (1980-2009) represents the recent past, the second (2010-2039) the near future, the third (2040-2069) the mid-century and the last one (2070-2099) representing the end century.
2 citations
TL;DR: In this article , the authors provided guidelines for the convergence of most probable maximum (MPM) wave crest heights and MPM green water wave impact forces on a ferry with a single course.
2 citations
TL;DR: In this article , a set of laboratory experiments on the effect of waves and wave-induced currents on the input rate and cross-shore transport and dispersion of different types of plastic debris, including the macro and mesosizes, in addition to microplastics are presented.
2 citations
TL;DR: In this article , a classification framework for the time-series of significant wave height based on Transformer encoder (TF) and empirical mode decomposition (EMD) is developed, which can provide a lead time of 6 to 48 h with the fixed thresholds of 2 m for high level waves and 1.5 m for low level waves.
2 citations
TL;DR: In this article , a series of experiments were conducted under regular wave conditions to analyze the wave protection and motion response performances, and the effects of mounting position, mounting rows, plate porosity, and protruding plate height were examined.
2 citations
TL;DR: In this paper , a reduced-scale mobile-bed model is employed in a series of flume experiments to investigate the evolution of a submerged berm under low-energy irregular waves.
2 citations
TL;DR: In this paper , the authors applied artificial neural network-based methodology to predict the breaker height (Hb) and found that the developed models are more reliable than existing models not only in overall cases but also in any slope range (horizontal, gentle, intermediate, and steep slope).
2 citations
TL;DR: In this paper , a combined study on guidance for the convergence and variability of wave crests and impact loading extreme values is presented, with focus on deriving the number of seeds and exposure durations required for a reliable estimate of design loads.
2 citations
TL;DR: In this paper , a deep learning model based on the deep learning, which is named driving field forced convolution long and short memory network (DFF-ConvLSTM), was proposed for predicting the sea wave.
2 citations
TL;DR: In this paper , the effect of various forms of currents on regular nonlinear waves in shallow water is investigated by use of a computational fluid dynamics approach, and the current profiles are considered in both following and opposing directions of the incoming wave, forming in total 18 wave currents configurations.
TL;DR: In this article , a barotropic numerical 3D model is used to investigate wave dynamics during a cyclone-induced storm-surge event, and the model is calibrated and validated for Cyclone Sidr (2007) and applied to ten idealized cyclonic scenarios.
Abstract: The Ganges-Brahmaputra-Meghna delta, located in the southern part of Bangladesh, is periodically exposed to severe tropical cyclones. It is estimated that two-fifths of the world’s total impact from tropical-cyclone-induced storm surges occur in this region, and these cause fatalities and economic losses every year. A barotropic numerical 3D model is used to investigate wave dynamics during a cyclone-induced storm-surge event. The model is calibrated and validated for Cyclone Sidr (2007) and applied to ten idealized cyclonic scenarios. Numerical experiments with different coupling configurations are performed to understand wave–current interactions on significant wave heights. Results show that the water level is the dominant factor in significant wave height modulation when the wave propagates into shallower regions from the deeper ocean, whereas the current modulates the deep ocean wave height. The WCI causes higher significant wave heights in shallower waters close to the coast compared with the deep ocean. Wave energy dissipation related to whitecapping processes plays a greater role in reducing the wave height nearshore than the dissipation due to depth-induced breaking and bottom friction in the GBMD during a cyclone-induced storm-surge event.
TL;DR: In this paper , a typical plunging breaker propagating over both the flooding (shoreward) and the ebbing (seaward) tides are tested, respectively, and compared to the scenario without tidal current (wave only).
TL;DR: In this paper , the authors investigated loads of a 1:10-scaled bridge deck with air vents concerning different clearance, wind velocity, and incident wave height, and found that the suppression efficiency of total vertical and horizontal forces could reach 60% and 40% with an opening ratio of 1%, respectively.
TL;DR: In this article , a wave sensor module (MOTUS Wave Sensor, Aanderaa Data Instruments) installed on a navigational buoy (Tideland) and a coastal buoy (EMM2.0) is validated against a dedicated wave measurement buoy (Waverider, Datawell).
TL;DR: In this article , the physical model tests for measuring the wave overtopping have been conducted with the foreshore slope in front of the seawall and the bottom seabed for the coastal road area was fabricated at the wave flume for two areas in the East sea areas.
Abstract: Wave overtopping rate is one of the most important design parameters for coastal structures. In this study, the physical model tests for measuring the wave overtopping have been conducted with the foreshore slope in front of the seawall. The bottom seabed for the coastal road area was fabricated at the wave flume for two areas in the East sea areas. The wave overtopping rate was measured for various water depths and wave conditions in each coastal area. In particular, the impulsive wave conditions were compared with the previous research and the similar trends of wave overtopping was observed. It could be known that the effect of foreshore slope was significant and should be concerned for applying theses formula like EurOtop.
TL;DR: In this paper , a case study of Hurricane Michael was used to evaluate the effect of sea level rise on hurricane wave heights. And the results indicated that the dynamically-coupled SWAN-ADCIRC models substantially enhance the modeling accuracy.
TL;DR: In this paper , the authors compared different methods such as Maximum Likelihood, L-moment and least square methods to estimate the parameters of Generalized Pareto Distribution (GPD), Gumbel, and Weibull distributions in order to determine 100 years return period wave height at 16 selected points within the Persian Gulf.
TL;DR: In this article , an experimental investigation of the interaction between a wave and an oscillating buoy (including wave breaking, wave run-up, and relative motion between waves and buoys) is conducted under constant power take-off (PTO) values.
TL;DR: In this article , an S-shaped wave energy converter (SB-WEC) was designed to assist near-zero-energy oceanography, which comprises a non-linear mechanical power take-off (PTO) and a novel Sshaped buoy (SB) for operation in the wave climate of the National Shallow Sea Comprehensive Test Site in China.
TL;DR: In this article , a floating buoy is developed using a MEMS inertial measurement unit and an IoT microcontroller, and the changes in threeaxis acceleration and three-axis gyroscope signals are analyzed using ML-based classification models to accurately predict wave height.
Abstract: Wave height is a critical consideration in the planning and execution of maritime projects. Wave height forecasting methods include numerical and machine learning (ML) techniques. The traditional process involves using numerical wave prediction models, which are very successful but are highly complex as they require adequate information on nonlinear wind–wave and wave–wave interactions, such as the wave energy-balance equation. In contrast, ML techniques can predict wave height without prior knowledge of the above-mentioned complex interactions. This research aims to predict wave height using micro-electromechanical systems (MEMS), internet of things (IoTs), and ML-based approaches. A floating buoy is developed using a MEMS inertial measurement unit and an IoT microcontroller. An experiment is conducted in which the developed buoy is subjected to different wave heights in real time. The changes in three-axis acceleration and three-axis gyroscope signals are acquired by a computer via IoT. These signals are analyzed using ML-based classification models to accurately predict wave height. The obtained validation accuracy of the ML models K-NN (K-nearest neighbor), support vector machine, and the bagged tree is 0.9906, 0.9368, and 0.9887 respectively, which indicates that MEMS and IoT can be used to accurately classify and predict wave heights in real-time.
TL;DR: In this paper , the authors evaluated the dependence of the difference between ERA5 wave data and buoy data on the Lagrangian surface current speeds derived from the drifting buoy positions, and found that the difference increases as the surface current speed increases.
Abstract: Drifting buoys can measure wave data even in areas far from land and with strong currents, such as the western boundary current. We evaluated the dependence of the difference between ERA5 wave data and buoy data on the Lagrangian surface current speeds derived from the drifting buoy positions. The ERA5 wave data does not consider the effects of ocean currents. The difference between the ERA5 wave heights and the buoy wave heights increases as the surface current speed increases. The ERA5 wave height is notably underestimated in the case of the opposing current to the mean wave direction, and the wave height is overestimated in the case of the following current to the mean wave direction. The magnitude of them is up to 20%. The wave periods from ERA5 data and the drifting buoy also have differences in the case of opposing and following currents, mainly due to the Doppler shift. Marked over- and underestimation of the ERA5 wave heights can be observed at higher surface current speeds in the Kuroshio extension area, where currents are influenced by mesoscale eddies. Overestimation and underestimation of the ERA5 wave heights are also frequent in the Kuroshio area.
TL;DR: In this article , the authors compare two leading global wave reanalyses against 326 coastal buoys, demonstrating that both re-analyses consistently underestimate significant wave height, 50-year return period and mean wave period in most coastal locations around the world.
Abstract: Abstract The analysis of extreme wave conditions is crucial for understanding and mitigating coastal hazards. As global wave reanalyses allow to extend the evaluation of wave conditions to periods and locations not covered by in-situ measurements, their direct use is common. However, in coastal areas, the accuracy of global reanalyses is lower, particularly for extreme waves. Here we compare two leading global wave reanalyses against 326 coastal buoys, demonstrating that both reanalyses consistently underestimate significant wave height, 50-year return period and mean wave period in most coastal locations around the world. Different calibration methods applied to improve the modelled extreme waves, resulting in a 53% reduction in the underestimation of extreme wave heights. Importantly, the 50-year return period for significant wave height is improved on average by 55%. Extreme wave statistics determined for coastal areas directly from global wave reanalyses require careful consideration, with calibration largely reducing uncertainty and improving confidence.
TL;DR: In this paper , the authors presented an analysis of the significant wave height parameter for the particular case of the Black Sea basin using satellite altimetry measurements from five different satellites taken from the IMOS (Integrated Marine Observing System) database.
Abstract: Significant wave height (Hs) data are essential in different scientific studies regarding coastal and marine environments, coastal management, various economic activities nearshore and offshore, as well as in the use of marine renewable energy, oil and gas offshore platform operation and security, safety of personnel and equipment. The current paper presents an analysis of the significant wave height parameter for the particular case of the Black Sea basin. In order to achieve this analysis, satellite altimetry measurements from five different satellites taken from the IMOS (Integrated Marine Observing System) database were used and compared with the results of SWAN model simulations in order to assess the accuracy of simulated Hs values. The analysis was performed on data available for a period of 3 years, from 2018 to 2020. The comparison of the simulated significant wave height with data measured by altimetry satellites showed a good correlation of 0.8. The obtained results bring a contribution with regards to a better insight and knowledge into the characteristics of wind waves in the Black Sea.
TL;DR: In this article , a wave scatter-diagrams, describing the joint probability of wave height and wave period worldwide, has been developed to provide a practical and representative wave input for the design of structures subjected to waves.
TL;DR: In this paper , a 3D scanning lidar, trinocular camera stereo processing and in situ measurements were used to study short-crested wave field breaking characteristics in the laboratory, yielding a dataset with dense spatio-temporal coverage relative to prior laboratory or field measurements.
TL;DR: In this article , the authors analysed just two years of UAV surveys over a single eroding beach-dune system (Victoria, Australia), in order to assess its utility in understanding the drivers of change.
TL;DR: In this article , the wave runup on pocket gravel beaches, in limited-fetch environment, which can be found around Mediterranean, has been studied and the variability is due to beach orientation and alignment of beach profiles to the prevailing wave direction, as well as difference in beach slope.
Abstract: Most empirical equations used for wave runup predictions have been developed from measurements at straight sandy beaches in unlimited fetch environments. While there are empirical equations to predict wave runup on gravel beaches, they have not been tested for prediction of wave runup on pocket gravel beaches, in limited-fetch environment, which can be found around Mediterranean. This paper addresses this lack of measurements on this type of beaches and examines the alongshore variability of wave runup. Wave runup measurements were made using video observations along 3 cross-sectional profiles on the pocket beach of Ploče, Croatia. The measurements have shown that the wave runup can vary for about 71% even around the centerline of the pocket beach. This variability is due to beach orientation and alignment of beach profiles to the prevailing wave direction, as well as difference in beach slope. Comparison of wave runup predictions from five well-known empirical equations and field measurements showed significant underprediction (up to NBIAS = −0.33) for energetic wave events, and overall high scatter (up to NRMSE = 0.38). The best performing wave runup equation was used for further refinement outside the original parameter space by including the Goda wave peakedness parameter (Qp). The newly developed empirical equation for wave runup reduced the NBIAS to 0 and the NRMSE by 31% compared to the original equation (developed equation metrics: R = 0.91, NBIAS = 0, NRMSE = 0.2, HH = 0.2 on the study site). This empirical equation can potentially be used for design of coastal structures and artificial beaches in similar environments, but further measurements are needed to test its applicability to a range of forcing and environmental conditions.
TL;DR: In this paper , a singular spectrum analysis (SSA) is proposed as a decomposition procedure to decompose measured data effectively into its deterministic and stochastic components, and the prediction accuracy of three distinct models is contrasted by means of diagnostic metrics, Mean Square Error (MSE), the Nash-Sutcliffe Coefficient of efficiency (CE), and determination of coefficient (R2).