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Empirical relationship between significant wave period and wave energy period in the coastal waters of China
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作者 Yuhuan Xue Chuanjiang Huang +2 位作者 Gang Wang Dejun Dai Fangli Qiao 《Acta Oceanologica Sinica》 2025年第1期50-58,共9页
Significant wave period is an important parameter in coastal and offshore engineering design.Traditional spectral wave models do not directly calculate this parameter,which means that it needs to be estimated from the... Significant wave period is an important parameter in coastal and offshore engineering design.Traditional spectral wave models do not directly calculate this parameter,which means that it needs to be estimated from the spectral periods using empirical formulas.The wave energy period is one of the wave periods directly output by many wave models and is often used in studies of wave energy.This study investigated the relationship between significant wave period and wave energy period using wave data measured at three stations in the coastal waters of China.The observations recorded at these stations in the South China Sea,the East China Sea,and the Bohai Sea covered a wide range of surface wave conditions.Analysis indicated that the ratio of significant wave period to wave energy period is closely related to the Goda peakedness parameter of the wave spectra.Therefore,we proposed an empirical formula in which significant wave period is a function of wave energy period and the Goda peakedness parameter.Evaluation results showed that the performance of this formula is substantially better than that of fitting formulas that use constant coefficients. 展开更多
关键词 surface waves significant wave period wave energy period wave spectral parameter wave spectra
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Review of Wave Energy Resource Characterisation,Metrics,and Global Assessments
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作者 Sara Ramos-Marin C.Guedes Soares 《哈尔滨工程大学学报(英文版)》 2025年第1期53-75,共23页
This paper provides an overview of the global wave resource for energy exploration.The most popular metrics and estimators for wave energy resource characterization have been compiled and classified by levels of energ... This paper provides an overview of the global wave resource for energy exploration.The most popular metrics and estimators for wave energy resource characterization have been compiled and classified by levels of energy exploration.A review of existing prospective wave energy resource assessments worldwide is also given,and those studies have been collated and classified by continent.Finally,information about forty existing open sea wave energy test sites worldwide and their characteristics is depicted and displayed on a newly created global map.It has been found that wave power density is still the most consensual metric used for wave energy resource assessment purposes among researchers.Nonetheless,to accomplish a comprehensive wave resource assessment for exploitation,the computation of other metrics at the practicable,technical,and socio-economic levels has also been performed at both spatial and temporal domains.Overall,regions in latitudes between 40°and 60°of both hemispheres are those where the highest wave power density is concentrated.Some areas where the most significant wave power density occurs are in offshore regions of southern Australia,New Zealand,South Africa,Chile,the British Isles,Iceland,and Greenland.However,Europe has been the continent where most research efforts have been done targeting wave energy characterisation for exploitation. 展开更多
关键词 Marine energy wave resource assessment wave energy converter Numerical wave models wave power density WEC performance
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Numerical Simulation of the Attack of Landslide-Generated Waves on a Vertical Wall
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作者 ZHENG Fei-dong HU Ya-an 《China Ocean Engineering》 2025年第1期125-134,共10页
In channel reservoirs,a quantitative characterization of landslide-generated impulse wave-structure interactions is essential for evaluating potential damage to infrastructure and dams.In this study,the problem of lan... In channel reservoirs,a quantitative characterization of landslide-generated impulse wave-structure interactions is essential for evaluating potential damage to infrastructure and dams.In this study,the problem of landslide-generated impulse waves that attack a vertical wall was investigated in a wave channel via a smooth particle hydrodynamics(SPH)method coupled with a Chrono model.The results indicated that the longitudinal velocity beneath the leading wave crest of an incident impulse wave deviated significantly from solitary wave theory.Moreover,the variation rate in the vertical velocity along the water column coincided with the theoretical prediction only for small wave amplitudes.Nevertheless,the maximum run-up height of an impulse wave can be accurately predicted via the solitary wave theory.Moreover,the maximum wall force during impulse wave-wall interaction was significantly larger than that during solitary wave reflection,particularly for high incident wave amplitudes.Overall,the present study demonstrated some striking differences in the interactions of landslide-generated impulse waves and solitary waves with a vertical wall. 展开更多
关键词 channel reservoirs landslide-generated impulse waves solitary waves wave-structure interaction wave reflection
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Verification and validation of a numerical wave tank with momentum source wave generation
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作者 Housheng Zhang Yijing Hu +1 位作者 Biao Huang Xin Zhao 《Acta Mechanica Sinica》 2025年第3期23-38,共16页
systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have bee... systematic verification and validation(V&V)of our previously proposed momentum source wave generation method is performed.Some settings of previous numerical wave tanks(NWTs)of regular and irregular waves have been optimized.The H2-5 V&V method involving five mesh sizes with mesh refinement ratio being 1.225 is used to verify the NWT of regular waves,in which the wave height and mass conservation are mainly considered based on a Lv3(H s=0.75 m)and a Lv6(H s=5 m)regular wave.Additionally,eight different sea states are chosen to validate the wave height,mass conservation and wave frequency of regular waves.Regarding the NWT of irregular waves,five different sea states with significant wave heights ranging from 0.09 m to 12.5 m are selected to validate the statistical characteristics of irregular waves,including the profile of the wave spectrum,peak frequency and significant wave height.Results show that the verification errors for Lv3 and Lv6 regular wave on the most refined grid are−0.018 and−0.35 for wave height,respectively,and−0.14 and for−0.17 mass conservation,respectively.The uncertainty estimation analysis shows that the numerical error could be partially balanced out by the modelling error to achieve a smaller validation error by adjusting the mesh size elaborately.And the validation errors of the wave height,mass conservation and dominant frequency of regular waves under different sea states are no more than 7%,8% and 2%,respectively.For a Lv3(H_(s)=0.75 m)and a Lv6(H_(s)=5 m)regular wave,simulations are validated on the wave height in wave development section for safety factors FS≈1 and FS≈0.5-1,respectively.Regarding irregular waves,the validation errors of the significant wave height and peak frequency are both lower than 2%. 展开更多
关键词 Verification and validation wave generation Momentum source function Regular wave Irregular wave Uncertainty estimation
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Analytical and Numerical Investigation of Primary and Cross Waves in a Flume with Double Shoals
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作者 WANG Gang XIN Song-gang +3 位作者 LI Chuan-zhong FU Rui-li ZHANG Yao SHI Hua-bin 《China Ocean Engineering》 2025年第2期290-302,共13页
Flume experiments play a pivotal role in studying wave propagation,with wave elements typically assumed to remain constant in the perpendicular direction.However,evident cross wave phenomena were observed within flume... Flume experiments play a pivotal role in studying wave propagation,with wave elements typically assumed to remain constant in the perpendicular direction.However,evident cross wave phenomena were observed within flumes under certain conditions.This paper presents new analytical solutions for both primary and cross waves on double shoals in a flume via linear shallow-water equations,which may be used to idealize dynamic experimental configurations of coral reefs.The primary waves on double shoals are described by the associated Legendre functions,whereas the ultimate solutions are derived by considering the incident and reflected waves in front of a bathymetry and the transmitted waves positioned behind it.The effects of the angular frequency and topographic parameters on the primary waves are subsequently analyzed.Cross waves on double shoals constitute a type of topographically trapped wave whose solutions are formulated by combining the first and second types of the associated Legendre functions.The angular frequency is not only determined by the wavenumber but also influenced by the topographic parameters.Numerical experiments are conducted to investigate the generation mechanism of cross waves.The consistency between the numerical results and analytical solutions confirms the validity of the new analytical framework of cross waves on double shoals. 展开更多
关键词 cross waves primary waves analytical solutions wave flume numerical experiments
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The Period and Phase Speed of Upper-tropospheric Planetary-and Synoptic-scale Waves during the Solstice Seasons:Climatology and Trends during 1979–2023
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作者 Zhixiang LI Jianhua LU Yimin LIU 《Advances in Atmospheric Sciences》 2025年第11期2223-2234,共12页
By applying the convolution-based Hilbert transform in the zonal direction on six-hourly streamfunction fields at200 h Pa, we present the climatology and trends of the local wave period, and zonal and meridional phase... By applying the convolution-based Hilbert transform in the zonal direction on six-hourly streamfunction fields at200 h Pa, we present the climatology and trends of the local wave period, and zonal and meridional phase speeds, of Rossby waves over the globe during the solstice seasons of 1979–2023. While partly similar to and inspired by Fragkoulidis and Wirth(2020), our method differs in its ability to cover both planetary-scale and synoptic-scale waves over not only the extratropics, but also the tropics and subtropics. Based on a physically reasonable global distribution of wave periods, our key new finding is a robust prolonging of wave periods over most regions of the tropics and subtropics during both solstice seasons of 1979–2023, except for the tropical Atlantic, which experiences a shortened wave period during June–July–August of 1979–2022. Both the prolonging and shortening of wave periods are mainly associated with the changes in planetary-scale waves. Regionally varying trends of the zonal phase speed(Cpx) of synoptic waves are consistent in sign with, but smaller in magnitude than, the trends of local zonal wind, confirming the conclusion of Wu and Lu(2023)on the opposite effects of zonal wind and the meridional gradient of potential vorticity on Cpx. Meanwhile, the Cpx trends of planetary-scale waves are relatively weak, and do not exhibit a robust relation with the trend of zonal wind. These new results are helpful toward better understanding the changes in atmospheric waves and extreme events under global warming. 展开更多
关键词 planetary waves synoptic waves wave period phase speed
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Long-Term Trends of Extreme Waves Based on Observations from Five Stations in China
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作者 Liwei Cao Shouhua Liu +6 位作者 Jian Zeng Shufang Qin Zhen Zhang Gang Wang Jinhai Zheng Qiuhua Liang Aifeng Tao 《哈尔滨工程大学学报(英文版)》 2025年第3期479-491,共13页
Extreme waves may considerably impact crucial coastal and marine engineering structures. The First Scientific Assessment Report on Ocean and Climate Change of China and The Fourth Assessment Report on Climate Change o... Extreme waves may considerably impact crucial coastal and marine engineering structures. The First Scientific Assessment Report on Ocean and Climate Change of China and The Fourth Assessment Report on Climate Change of China were published in 2020 and 2022, respectively.However, no concrete results on the long-term trends in wave changes in China have been obtained. In this study, long-term trends in extreme wave elements over the past 55 years were investigated using wave data from five in situ observation sites(i.e., Lao Hu Tan, Cheng Shan Tou,Ri Zhao, Nan Ji, Wei Zhou) along the coast of China. The five stations showed different trends in wave height. Results show a general downward trend in wave heights at the LHT and CST stations, reaching-0.78 and-1.44 cm/a, respectively, in summer at middle and high latitudes. NJI stations at middle-to-low latitudes are influenced by the winter monsoon and summer tropical cyclones, showing a substantial increase in extreme wave heights(0.7 cm/a in winter and 2.68 cm/a in summer). The cumulative duration of H_(1/10) ≥ 3 m at NJI and RZH has grown since 1990. 展开更多
关键词 Maximum wave height Long-term trend wave climate seasonal variability Extreme wave Generalized extreme value
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Characteristics of hypersonic inward turning detonation wave
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作者 Haochen XIONG Ruofan QIU +2 位作者 Tao ZHANG Hao YAN Yancheng YOU 《Chinese Journal of Aeronautics》 2025年第4期142-154,共13页
The selection of an appropriate basic detonation wave flow field is crucial for improving the performance and geometric design of standing detonation vehicles.This paper employs a detailed chemical reaction model and ... The selection of an appropriate basic detonation wave flow field is crucial for improving the performance and geometric design of standing detonation vehicles.This paper employs a detailed chemical reaction model and solves the unsteady axisymmetric Euler equation to study the characteristics of the Axisymmetric Inward Turning Curved Detonation Wave(AIT-CDW)flow field and the parameters affecting the stability of the wave system structure of AIT-CDW flow field.The numerical results demonstrate a radial compression effect in the AIT-CDW flow field.This effect causes the detonation wave to have a shorter initiation length than oblique detonation wave flow field and the detonation wave angle to gradually increase with the flow direction postdetonation.The AIT-CDW flow field is confined space,making it prone to normal detonation waves when the detonation wave reflects from the wall.This phenomenon is detrimental to the stability of the wave system structure in the flow field.It has been observed that increasing the center body radius and decreasing the fuel equivalent ratio can effectively reduce the height of the normal detonation wave or even eliminate it.Additionally,a well-designed generatrix shape of the center body can enhance airflow,reduce choked flow,and promote the stability of the wave structure in the flow field. 展开更多
关键词 Axisymmetric inward turning detonation wave Basic detonation flow field Radial compression effect wave structures Detonation wave reflection
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Uncovering Hidden Spin of Scalar Fields with Higher-Order Derivative Lagrangian:On the Wave Spin in Drifted and Dissipative Fields
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作者 Shuo Xin Mengxiang Xie Jie Ren 《Chinese Physics Letters》 2025年第6期70-77,共8页
Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand ... Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand elastic longitudinal waves,which are of irrotational curl-free nature without vorticity and can be describedby scalar fields.Moreover,the conventional theory cannot even answer the question of whether wave spin existsin dissipative fields,given the ubiquitous dissipation in reality.Here,to resolve the seeming paradox and answerthe challenging question,we uncover the origin of wave spin in scalar fields beyond traditional formalism byclarifying that the presence of higher-order derivatives in scalar field Lagrangians can give rise to non-vanishingwave spin.For“spinless”scalar fields of only first-order derivatives,we can make the hidden wave spin emergeby revealing a latent field that leads to the original field through a time derivative,thus giving higher-order termsin Lagrangian.Based on the standard Noether theorem approach,we exemplify the wave spin for unconventionaldrifted acoustic fields,and even for dissipative media,in scalar fields with higher-order derivative Lagrangian.The results would prompt people to build more comprehensive and fundamental understandings of structuralwave spin in classical fields. 展开更多
关键词 higher order derivative Lagrangian hidden spin acousticand elastic longitudinal waveswhich acoustic waves wave spin spin angular momentum scalar fields
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Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes 被引量:1
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作者 Changjiang Liu Hujun Li +3 位作者 Zhen Wang Yong He Guokai Zhang Mingyang Wang 《Defence Technology(防务技术)》 2025年第1期120-141,共22页
Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads ... Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion,which can damage personnel and equipment.Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics.The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation.Based on the experimental and numerical simulation results,a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established.The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition.In contrast,an increase in altitude accelerated the propagation speed of the shock wave in the tunnel.The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than15%,the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%.The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes. 展开更多
关键词 Shock wave propagation TUNNEL Altitude effect Peak overpressure Shock waves velocity Engineering safety
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Efficient multi-millijoule THz wave generation from laser interactions with a cylindrical GaAs waveguide
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作者 Zahra Ghanavati Hamid Reza Zangeneh 《红外与毫米波学报》 北大核心 2025年第4期586-593,共8页
This study involved a comprehensive investigation aimed at achieving efficient multi-millijoule THz wave generation by exploiting the unique properties of cylindrical GaAs waveguides as effective mediators of the conv... This study involved a comprehensive investigation aimed at achieving efficient multi-millijoule THz wave generation by exploiting the unique properties of cylindrical GaAs waveguides as effective mediators of the conversion of laser energy into THz waves.Through meticulous investigation,valuable insights into optimizing THz generation processes for practical applications were unearthed.By investigating Hertz potentials,an eigen-value equation for the solutions of the guided modes(i.e.,eigenvalues)was found.The effects of various param-eters,including the effective mode index and the laser pulse power,on the electric field components of THz radia-tion,including the fundamental TE(transverse electric)and TM(transverse magnetic)modes,were evaluated.By analyzing these factors,this research elucidated the nuanced mechanisms governing THz wave generation within cylindrical GaAs waveguides,paving the way for refined methodologies and enhanced efficiency.The sig-nificance of cylindrical GaAs waveguides extends beyond their roles as mere facilitators of THz generation;their design and fabrication hold the key to unlocking the potential for compact and portable THz systems.This trans-formative capability not only amplifies the efficiency of THz generation but also broadens the horizons of practical applications. 展开更多
关键词 terahertz waves cylindrical waveguides gallium arsenide(GaAs)matter nonlinear optical processes multi-millijoule THz pulses
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Receptivity of a hypersonic blunt cone boundary layer to freestream entropy and vorticity waves
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作者 Menghao Niu Caihong Su 《Acta Mechanica Sinica》 2025年第6期93-104,共12页
Hypersonic boundary-layer receptivity to freestream entropy and vorticity waves is investigated using direct numerical simula-tions for a Mach 6 flow over a 5.08 mm nose radius cone.Two frequencies of 33 kHz and 150 k... Hypersonic boundary-layer receptivity to freestream entropy and vorticity waves is investigated using direct numerical simula-tions for a Mach 6 flow over a 5.08 mm nose radius cone.Two frequencies of 33 kHz and 150 kHz are considered to be rep-resentative of the first and second instability modes,respectively.For the first mode,wall pressure fluctuations for both entropy and vorticity wave cases exhibit a strong modulation yet without a growing trend,indicating that the first mode is not generated despite its instability predicted by linear stability theory.The potential reason for this is the absence of postshock slow acoustic waves capable of synchronizing with the first mode.By contrast,for the second mode,a typical three-stage boundary-layer response is observed,consistent with that to slow acoustic waves studied previously.Furthermore,the postshock disturbances outside the boundary layer can be decomposed into the entropy(density/temperature fluctuations)and vorticity components(ve-locity fluctuations),and the latter is shown to play a leading role in generating the second mode,even for the case with entropy waves where the density/temperature fluctuations dominate the postshock regions. 展开更多
关键词 HYPERSONIC Boundary layer RECEPTIVITY Entropy wave Vorticity wave
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Response characteristics of shear waves scattered by fractures with borehole observation system
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作者 Peng Liu Hua-Jun Fan +4 位作者 Meng-Sheng Zhang Zhen Li Jing-Wei Jiang Yuan Gao Ke-Wen Wang 《Petroleum Science》 2025年第5期1912-1928,共17页
Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as ... Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as fracture length and dip angle are the focus of geophysical work.In borehole observation system,the short distance between fractures and detectors leads to weak attenuation of elastic wave energy,and high-frequency source makes it easier to identify small-scale fractures.Compared to traditional monopole logging methods,dipole logging method has advantage of exciting pure shear waves sensitive to fractures,so its application is becoming increasingly widespread.However,since the reflected shear waves and scattered shear waves of fractures correspond to different fracture properties,how to distinguish and analyze these two kinds of waves is crucial for accurately characterizing the fracture parameters.To address this issue,numerical simulation of wave responses by a single fracture near a borehole in rock formation is performed,and the generation mechanism and characteristics of shear waves scattered by fractures are investigated.It is found that when the dip angle of the fracture surpasses a critical threshold,the S-wave will propagate to both endpoints of the fracture and generate scattered S-waves,resulting in two distinct scattered wave packets on the received waveform.When the polarization direction of the acoustic source is parallel to the strike of the fracture,the scattered SH-waves always have larger amplitude than the scattered SV-waves regardless of changing the fracture dip angle.Unlike SV-waves,the SH-waves scattered by the fracture do not have any mode conversion.Additionally,propagation of S-waves to a short length fracture can induce dipole mode vibration of the fracture within a wide frequency range.The phenomena of shear waves reflected and scattered by the fracture are further illustrated and verified by two field examples,thus showing the potential of scattered waves for fracture evaluation and characterization with borehole observation system. 展开更多
关键词 Numerical modeling wave scattering Shear wave FRACTURES Borehole observation system
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2D Hydrodynamic Performance of a Bottom-Hinged Flap Breakwater:Pitching Motion Response Under Random Waves and Comparison with Regular Waves
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作者 YIN Zegao LI Feifan +1 位作者 ZHANG Chao LI Guoqing 《Journal of Ocean University of China》 2025年第5期1206-1222,共17页
To propel the application of a bottom-hinged flap breakwater in real sea conditions,a two-dimensional computational fluid dynamics numerical model was conducted to investigate the pitching motion response and wave att... To propel the application of a bottom-hinged flap breakwater in real sea conditions,a two-dimensional computational fluid dynamics numerical model was conducted to investigate the pitching motion response and wave attenuation in random waves.First,the flow velocity distribution characteristic of the pitching flap at typical times was summarized.Then,the effects of random wave and flap parameters on the flap’s significant pitching angle amplitude θ_(s) and hydrodynamic coefficients were investigated.The results reveal that θ_(s) and wave reflection coefficient K_(r) values increase with increasing significant wave height Hs,random wave steepnessλs,and flap relative height.As Hs andλs increase,the wave transmission coefficient K_(t) increases while the wave dissipation coefficient K_(d) decreases.Additionally,K_(t) decreases with increasing flap relative height.With increasing equivalent damping coefficient ratio,θ_(s) and K_(t) decrease,while K_(r) and K_(d) increase.The relationships betweenλs and flap relative height on the one hand andθ_(s),K_(r),K_(t),and K_(d) in random waves on the other hand are compared to those in regular waves.Based on the equal incident wave energy and the equal incident wave energy flux,the pitching flap performs better in the wave attenuation capability under random waves than in regular waves.Finally,the dimensionless parameters with respect to random wave and flap were used to derive the K_(r) and K_(t) for-mulae,which were validated with the related data. 展开更多
关键词 pitching flap pitching angle amplitude hydrodynamic coefficients random waves regular waves
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Microscopic Evidence of Charge-and Spin-Density Waves in La_(3)Ni_(2)O_(7-δ)Revealed by^(139)La-NQR
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作者 Jun Luo Jie Feng +7 位作者 Gang Wang Ningning Wang Jie Dou Aifang Fang Jie Yang Jinguang Cheng Guoqing Zheng Rui Zhou 《Chinese Physics Letters》 2025年第6期216-228,共13页
The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)tran... The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)transition occurring near the superconducting dome.Identifying the type of DW order is crucial for understanding the origin of superconductivity in this system.However,owing to the presence of La4Ni3O10 and other intergrowth phases in La_(3)Ni_(2)O_(7-δ)samples,extracting the intrinsic information from the La_(3)Ni_(2)O_(7) phase is challenging.In this study,we employed ^(139)La nuclear quadrupole resonance(NQR)measurements to eliminate the influence of other structural phases in the sample and obtain microscopic insights into the DW transition in La_(3)Ni_(2)O_(7-δ).Below the DW transition temperature T_(DW)∼153 K,we observe a distinct splitting in the±5/2↔±7/2 transition of the NQR resonance peak at the La(2)site,while only a line broadening is seen in the±3/2↔±5/2 transition peak.Through further analysis of the spectra,we show that the line splitting is due to a unidirectional charge modulation.A magnetic line broadening is also observed below T_(DW),accompanied by a large enhancement of the spin-lattice relaxation rate,indicating the formation of magnetically ordered moments in the DW state.Our results suggest a simultaneous formation of charge-and spin-density wave orders in La_(3)Ni_(2)O_(7-δ),thereby offering critical insights into the electronic correlations in Ni-based superconductors. 展开更多
关键词 spin density wave electronic correlations SUPERCONDUCTIVITY La Ni O charge density wave NQR
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Advance in Sea Surface Wind and Wave Retrieval from Synthetic Aperture Radar Image:An Overview
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作者 HAO Mengyu HU Yuyi +3 位作者 SHAO Weizeng MIGLIACCIO Maurizio JIANG Xingwei WANG Zhenyuan 《Journal of Ocean University of China》 2025年第4期821-839,共19页
Synthetic aperture radar(SAR)aboard SEASAT was first launched in 1978.At the beginning of the 21st century,the Chinese remote sensing community recognized the urgent need to develop domestic SAR capabilities.Unlike sc... Synthetic aperture radar(SAR)aboard SEASAT was first launched in 1978.At the beginning of the 21st century,the Chinese remote sensing community recognized the urgent need to develop domestic SAR capabilities.Unlike scatterometers and al-timeters,space-borne SAR offers high-resolution images of the ocean,regardless of weather conditions or time of day.SAR imagery provides rich information about the sea surface,capturing complicated dynamic processes in the upper layers of the ocean,particular-ly in relation to tropical cyclones.Over the past four decades,the advantages of SAR have been increasingly recognized,leading to notable marine applications,especially in the development of algorithms for retrieving wind and wave data from SAR images.This study reviews the history,progress,and future outlook of SAR-based monitoring of sea surface wind and waves.In particular,the ap-plicability of various SAR wind and wave algorithms is systematically investigated,with a particular focus on their performance un-der extreme sea conditions. 展开更多
关键词 sea surface wind wave synthetic aperture radar tropical cyclone wave breaking
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Different Types of Electrical Generators for Converting Wave Energy into Electrical Energy–A Review
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作者 Jawad Faiz Shahryar Haghvirdiloo Ali Ghaffarpour 《哈尔滨工程大学学报(英文版)》 2025年第1期76-97,共22页
This review paper examines the various types of electrical generators used to convert wave energy into electrical energy.The focus is on both linear and rotary generators,including their design principles,operational ... This review paper examines the various types of electrical generators used to convert wave energy into electrical energy.The focus is on both linear and rotary generators,including their design principles,operational efficiencies,and technological advancements.Linear generators,such as Induction,permanent magnet synchronous,and switched reluctance types,are highlighted for their direct conversion capability,eliminating the need for mechanical gearboxes.Rotary Induction generators,permanent magnet synchronous generators,and doubly-fed Induction generators are evaluated for their established engineering principles and integration with existing grid infrastructure.The paper discusses the historical development,environmental benefits,and ongoing advancements in wave energy technologies,emphasizing the increasing feasibility and scalability of wave energy as a renewable source.Through a comprehensive analysis,this review provides insights into the current state and future prospects of electrical generators in wave energy conversion,underscoring their potential to significantly reduce reliance on fossil fuels and mitigate environmental impacts. 展开更多
关键词 wave energy Rotary generators Linear generators Control systems wave energy converters
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Numerical Investigations on Evolution Characteristics of Sand Waves Under Current and Waves at Various Interaction Angles
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作者 ZANG Zhi-peng TIAN Rui +2 位作者 ZOU Xing XIE Bo-tao ZHANG Jin-feng 《China Ocean Engineering》 2025年第4期648-661,共14页
A three-dimensional numerical model of sand wave dynamics,incorporating the interaction of currents and waves at various angles,has been developed using the Regional Ocean Modeling System(ROMS).This model accounts for... A three-dimensional numerical model of sand wave dynamics,incorporating the interaction of currents and waves at various angles,has been developed using the Regional Ocean Modeling System(ROMS).This model accounts for both bedload and suspended load sediment transport under combined waves and current conditions.The investigation examines the influence of several key parameters,including the rotation angle of sand waves relative to the main current,tidal current velocity amplitude,residual current,water depth,wave height,wave period,and wave direction,on sand wave evolution.The growth rate and migration rate of sand waves decrease as their rotation angle increases.For rotation angles smaller than 15°,sand wave evolution can be effectively simulated by a vertical 2D model with an error within 10%.The numerical results demonstrate that variations in tidal current velocity amplitude or residual current affect both vertical growth and horizontal migration of sand waves.As tidal current velocity amplitude and residual current increase,the growth rate initially rises to a maximum before decreasing.The migration rate shows a consistent increase with increasing tidal current amplitude and residual current.Under combined waves and current,both growth and migration rates decrease as water depth increases.With increasing wave height and period,the growth rate and migration rate initially rise to maximum values before declining,while showing a consistent increase with wave height and period.The change rate of sand waves reaches its maximum when wave propagation aligns parallel to tidal currents,and reaches its minimum when wave propagation is perpendicular to the currents.This phenomenon can be explained by the fluctuation of total bed shear stress relative to the angle of interaction between waves and current. 展开更多
关键词 sand waves 3D numerical model tidal current waveS angles of interaction growth rate migration rate
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Global distributions and long-term trends of available wave energy based on ERA5 wave reanalysis
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作者 Jian Shi Wei Liu +5 位作者 Haifei Sun Xiangming Cao Yuan Li Chi Zhang Nguyen Viet Thanh Lipeng Zhang 《Acta Oceanologica Sinica》 2025年第6期15-32,共18页
Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wa... Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wave energy storage but is also affected by the local available wave probability.Different distributions and trends between the available wave energy and total wave energy storage are observed.Larger values of total wave energy storage are concentrated in the high-latitude westerlies zone,whereas available wave energy storage exhibits greater concentration in the middle-low latitude regions.In each basin,there is a notable upward trend in both total wave energy storage and available wave energy storage.However,the northern Hemisphere(NH)exhibits an increasing trend in available wave probability,whereas the southern Hemisphere(SH)experiences a decreasing trend.This divergence contributes to the spatial distributions of available wave energy storage becoming increasingly uniform.These trends in wave energy are primarily influenced by changes in significant wave height.Although the increasing trend of significant wave height across all frequency ranges induces the growth of total wave energy storage,only the increasing of wave heights falling in 1.3−4 m can cause the growth of available wave energy storage.The consistent increasing rates of wave height under different mean levels contribute to the divergent trends in available wave probability. 展开更多
关键词 ERA5 available wave energy spatial distribution long-term trends wave energy converter
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Research and Application of Scholte Wave Inversion Modeling Method for Marine OBN Multicomponent Oil and Gas Exploration
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作者 Zhang Hua Wang Guang-yin +1 位作者 Zhang Jian-lei Chen Hai-feng 《Applied Geophysics》 2025年第3期857-868,897,898,共14页
In multi-component oil and gas exploration using ocean bottom nodes,converted wave data is rich in lithological and fracture information.One of the urgent problems to be solved is how to construct an accurate shear wa... In multi-component oil and gas exploration using ocean bottom nodes,converted wave data is rich in lithological and fracture information.One of the urgent problems to be solved is how to construct an accurate shear wave velocity model of the shallow sea bottom by leveraging the seismic wave information at the fluid-solid interface in the ocean,and improve the lateral resolution of marine converted wave data.Given that the dispersion characteristics of surface waves are sensitive to the S-wave velocity of subsurface media,and that Scholte surface waves,which propagate at the interface between liquid and solid media,exist in the data of marine oil and gas exploration,this paper proposes a Scholte wave inversion and modeling method based on oil and gas exploration using ocean bottom nodes.By using the method for calculating the Scholte wave dispersion spectrum based on the Bessel kernel function,the accuracy of dispersion spectrum analysis is improved,and more accurate dispersion curves are picked up.Through the adaptive weighted least squares Scholte wave dispersion inversion algorithm,the Scholte wave dispersion equation for liquid-solid media is solved,and the shear wave velocity model of the shallow sea bottom is calculated.Theoretical tests and applications of realdata have proven that this method can significantly improve the lateral resolution of converted wave data,provide high-quality data for subsequent inversion of marine multi-component oil and gas exploration data and reservoir reflection information,and contribute to the development of marine oil and gas exploration technology. 展开更多
关键词 Ocean bottom node Converted wave Scholte wave Inverse modeling
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