基于ERA-Interim再分析数据的近35年中国海域波浪能资源评估

波浪能是一种可再生能源,对波浪能资源进行可靠的评估是开发利用的前提。本文利用欧洲中期天气预报中心(ECMWF)ERA-Interim 1981-2015年0.125°×0.125°的较高分辨率的海浪场数据,计算了中国海域的波浪能流密度,采用波浪能流密度的富集度频率和变异系数评价了中国海域的波浪能资源,系统研究了波浪能流密度的季节特征及富集度特征。研究表明:(1)我国周边海域波浪能资源呈现非常明显的季节分布特征,秋冬季较丰富、春夏季较贫乏。(2)波浪能资源的丰富的海区为海南岛以东、广东省以南海域(即南海中北部),同时,台湾岛东部海域波浪能资源也较为丰富。(3)波浪能资源相对稳定的区域为台湾岛以东海域和南海中北部海域,其中冬季稳定性最好,夏季最差。(4)综合考虑到波能资源开发的特点,建议选择广东沿岸海域作为波浪能开发的重点海域。     

山东省周边海域波浪能资源评估

采用第三代海浪模式SWAN对2001-2010年期间山东省周边海域的波浪状况进行了数值模拟。波浪能数值模拟值与台站观测值的比对结果表明模拟值可靠、实用。分析发现山东省周边海域平均波能流密度以2 000W/m以下为主,低于中国南部海域及欧美沿岸波能流密度。选取12个典型代表点,从波能流密度大小、变化特征、稳定性等角度分析了不同代表点的波浪能情况,发现山东周边波能流密度受气候变化影响近10年来呈上升趋势。综合不同区域波浪能大小及需求情况,建议选取山东半岛东部海域、蓬莱外围岛屿近渤海中部海域和渤海中部海域作为波浪能开发利用的首选区域。其中成山头东部海域波能流密度在冬季高达5 000 W/m,在该季节大部分区域可归为一类资源丰富区。基于此,建议开发利用中小规模的波浪能供电设备或供电设施。     

波浪能利用的发展与前景

文章首先介绍了波浪能的定义、成因和我国波浪能资源的分布情况。在此基础上,指出波浪能的主要利用方式是发电,并分析了国内外利用波浪能发电的发展进程。从波浪能的发电原理、转换装置及技术上的突破等方面,论述了波浪能发电的研究开发情况。最后,指出波浪能利用中存在的一些问题并对其发展前景进行了展望。     

波浪能利用的发展与前景

文章首先介绍了波浪能的定义、成因和我国波浪能资源的分布情况。在此基础上，指出波浪能的主要利用方式是发电，并分析了国内外利用波浪能发电的发展进程。从波浪能的发电原理、转换装置及技术上的突破等方面，论述了波浪能发电的研究开发情况。最后，指出波浪能利用中存在的一些问题并对其发展前景进行了展望。     

波浪能利用发展历史与关键技术

波浪能作为一种新型清洁能源,近年来得到各国的重视。文章从波浪能利用的发展历史、波浪能资源的评估手段、波浪能转换装置的种类及代表性装置等几个角度,对国内外研究现状进行了阐述;总结了波浪能发电技术中关于流体动力特性非线性计算、装置稳能技术、阵列发电场设计、与其它新能源结合应用等研究方向及技术难点;最后对波浪能利用技术的未来进行展望。     

基于ERA5的黄渤海附近海域波浪能资源时空特征分析

波浪能资源是一种重要的海洋可再生能源，开发利用波浪能资源可以有效的缓解常规能源短缺问题带来的能源问题以及环境污染问题。对波浪能资源进行科学评估是进行海洋能资源利用的前提条件，本文利用欧洲中期天气预报中心（European Centre for Medium-Range Weather Forecasting，ECMWF）第五代再分析数据集（ECMWF Reanalysis v5 ERA5），采用新的波浪能评估公式，对黄渤海海域1980—2018年间波浪能资源展开评估，主要计算指标包括波浪能可开发量频率、富集量频率、变异系数以及可利用波高占比等，结果显示：黄渤海区波浪能资源具有明显的季节性，秋冬季节较高，春夏季节较低，冬季是波浪能资源开发的最佳季节；波浪能富集区域主要集中在渤海海峡外侧、成山头东部以及长江口外海区域。在此基础上确定了波浪能资源的重点开发利用区，为后续的波浪能开发提供参考。     

中国大陆沿岸波浪能分布初步研究

波浪能作为可持续利用的清洁能源,日益被人们所关注,本文基于WAVEWATCHⅢ全球波浪模式,建立了较高精度的中国沿岸海域波浪数学模型,重点对中国大陆沿岸-30m等深线上的波浪能分布进行了研究,在已有研究成果的基础上进一步细化了中国沿岸海域波浪能的时空分布规律,为合理开发、利用波浪能提供了一定的数据支持。研究认为,中国沿岸波浪能储量相对较小,南北分布以长江口为界,以南海域波能整体较大,波能季节性差异明显,在开发利用时,需要对工程区域的波浪能特征充分论证,科学合理地选用波浪能转化设备,防止造成巨大经济损失。     

福建沿海海域波浪能资源分析与评价

采用波浪模拟的方法,较准确计算得出福建沿海海域波浪能资源分布状况,并给出相应的分析和综合评价.主要结论如下:(1)福建沿海海域波浪能平均密度为2.6～7.3 kW/m,波浪能资源储量为2 210.45 MW,在我国沿海海域仅次于台湾和广东,是波浪能开发利用可以优先考虑的海区之一.(2)福建沿海海域波浪能资源储量的70%分布于平潭岛以北海域,其值达1 512.49 MW.其中,尤以北礵地区值最大,为378.80 MW.(3)以年平均波高为指标,福建沿海海域中东山区段为三类区,其他区段均为一类区和二类区,具有良好的开发前景.(4)福建沿海海域波浪能具有波功率密度低、资源分布广泛且不均匀、波功率密度随季节变化、能量具有多向性等分布特点.(5)基于福建波浪能的开发与利用现状,建议应优先着眼于解决边远海岛等特殊场所的用电问题.     

基于高分辨率数值模拟技术的近海波浪能资源评估

采用SWAN模型,对浙江中部近海海域进行了为期10 a的高分辨率波浪数值模拟,获得了年均波功率密度分布,同时讨论了波能在该海域的有效时长分布,通过对波功率密度的变异系数统计讨论了其稳定性,最后估算了该海域波浪能资源储量约为0.91×10～6kW。总体而言,在近海海域中,离岸较近的浅海海域波能资源较为贫乏,波功率密度大于2 kW/m的海域多分布于10 m等深线以外,其等值线与岸线趋于平行;离大陆较远的岛屿周边海域波能资源丰富,在初期波浪能开发利用阶段具有明显的优势;近岸海域波浪能有效时长约1 500 h,至鱼山列岛一线离岸较远海域约4 000 h;近海大部分海面波浪能变异系数约在2-3之间。     

点吸收式波浪能发电装置姿态特性分析

点吸收式波浪能发电装置是一种最简单的振荡体式波浪能发电装置, 但其安装成本高、生存能力较差。本文针对点吸收式波浪能发电装置的姿态稳定性问题, 开展了其在波浪作用下的运动姿态和发电功率之间的关系研究。首先介绍了点吸收波浪能发电装置的工作原理; 然后,根据我国南海海域的自然资源条件, 划定波况范围, 利用相似理论在实验室中模拟波浪参数,选定工况, 建立模型, 设计测量系统, 开展物理模型试验; 最后, 利用试验结果分析了发电装置的最佳发电周期、波高对装置发电功率的影响, 装置姿态对发电功率的影响等。本文为点吸收式波浪能发电装置设计及测试提供了参考。     

Predictions of the hydrodynamic performance of the wave rotor wave energy device

This paper provides a linear solution for the Wave Rotor, a wave energy device that comprises two parallel counter rotating cylinders in orbital motion. Theoretical results are obtained for the radiated waves generated by the device, and for its efficiency. Comparisons with earlier measurements of radiated waves show very promising agreement.     

An approximate solution for the wave energy shadow in the lee of an array of overtopping type wave energy converters

In this study we investigate how the wave energy deficit in the lee of an array of overtopping type wave energy converting devices (WECs), redistributes with distance from the array due to the natural variability of the wave climate and wave structure interactions. Wave directional spreading has previously been identified as the dominant mechanism that disperses the wave energy deficit, reducing the maximum wave height reduction with increasing distance from the array. In addition to this when waves pass by objects such as an overtopping type WEC device, diffracted waves re-distribute the incident wave energy and create a complex interference pattern. The effect of wave energy redistribution from diffraction on the wave energy shadow in the near and far field is less obvious. In this study, we present an approximate analytical solution that describes the diffracted and transmitted wave field about a single row array of overtopping type WECs, under random wave conditions. This is achieved with multiple superpositions of the analytical solutions for monochromatic unidirectional waves about a semi-infinite breakwater, extended to account for partial reflection and transmission. The solution is used to investigate the sensitivity of the far field wave energy shadow to the array configuration, level of energy extraction, incident wave climate, and diffraction. Our results suggest that diffraction spreads part of the wave energy passing through the array, away from the direct shadow region of the array. This, in part, counteracts the dispersion of the wave energy deficit from directional spreading.     

On the capture width of wave energy converters

This paper extends the theory on capture width, a commonly used performance indicator for a wave energy converter (WEC). The capture width of a linear WEC is shown to depend on two properties: the spectral power fraction (a property introduced in this paper), which depends entirely on the sea state, and the monochromatic capture width, which is determined by the geometry of the WEC and the chosen power take off (PTO) coefficients. Each of these properties is examined in detail. Capture width is shown to be a measure of how well these two properties coincide. A study of the effects of PTO control on the capture width suggests that geometry control, a form of control that has not been the focus of much academic research, despite its use in the wave energy industry, deserves more attention. The distinction between geometry control and PTO control is outlined. While capture width is a valuable design tool, its limitations must be recognised. The assumptions made in the formulation of capture width are listed, and its limitations as a tool for estimating annual power capture of a WEC are discussed.     

利用波浪谱理论计算我国近岸波浪能方法研究

简述了当前被较多应用于我国近岸波浪能计算的简化公式会带来较大计算误差的事实,指出了这是因不合理假设和化简造成的结果。在此基础上,提出了利用波浪谱计算我国近岸波浪能的计算思路,同时利用波浪谱参量与实测数据比对,间接证明了该思路的合理性。     

Spectral modelling of wave energy converters

A spectral model suitable for the representation of wave energy converters is developed. A spectral model is an extension of a frequency-domain model that allows inclusion of non-linear forces and thereby provides improved estimates of wave energy converter performance, without the high computational cost of a time-domain model. The suitability and accuracy of a spectral model representation is demonstrated for a flap-type wave energy converter, by modelling the effect of vortex shedding and large amplitudes of motion. The development of a spectral model of wave energy converters also means that they can be represented in spectral wave models and included explicitly in software tools such as SWAN or Mike21 SW. This means that tools familiar to the industry could be used to determine the environmental impact and energy yield of wave farms efficiently.     

Rocking buoy wave energy converter

A device for converting ocean wave energy into electricity utilizing a rocking buoy and a hydrogen pressure cell is described. The moored buoy contains a pneumatic tube filled with a dense liquid which rocks back and forth as a result of the ocean wave activity. Hydrogen gas, maintained above the dense fluid is alternatively compressed and expanded by the moving fluid. The hydrogen gas communicates with a hydrogen pressure cell and the resulting pressure difference across the cell leads to an electrical voltage and under load, to electrical power.