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《中国海洋大学学报(自然科学版)》2015,(7)
叶片对潮流能水轮机的性能有很大的影响,因此对叶片进行优化研究对于提高潮流能水轮机的效率的重大意义。本文对50kW潮流能水平轴水轮机进行了叶片设计,针对水轮机具体的运行环境,以提高水轮机获能为目标,应用遗传算法对叶片弦长和扭角进行了优化设计。通过对比实际工况下水轮机的获能特性得知,优化的叶片获能系数和获能功率较原叶片有所提高,从而证明应用遗传算法进行叶片优化的可行性,为水轮机叶片优化提供了新的方法。 相似文献
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垂直轴潮流能水轮机具有结构简单、适应任意流向等优点,但其能量转换效率低于水平轴水轮机,在运行时有较大的转矩脉动,不利于水轮机的平稳运行,易引起结构疲劳。本文针对垂直轴潮流能水轮机的运行特点,提出了一种导流涵道装置,利用数值模拟方法对比分析水轮机在有无导流涵道装置情况下的水动力性能。结果表明,导流涵道可以起到整流的作用,使流体在水轮机盘面内的流动更加平顺。另外,导流涵道装置不仅可以提高水轮机的能量利用率,还能有效改善作用在水轮机叶片上的水力驱动力矩脉动和转速脉动,改善了水轮机运行状态,提高了结构可靠性。 相似文献
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四种重金属对刺参幼参的急性致毒效应 总被引：1，自引：0，他引：1
采用静水试验法,在水温18.5℃~20℃的条件下,用Cu2 ,Zn2 ,Cd2 和Cr6 四种重金属对刺参幼参进行了单一急性毒性试验。结果表明:Cu2 对刺参幼参的24h,48h,72h和96hLC50分别为0.299,0.176,0.133和0.120mg/L;Zn2 的24h,48h,72h和96hLC50分别为6.700,3.624,2.577和1.951mg/L;Cd2 的24h,48h和72hLC50分别为4.246,2.588和2.137mg/L;Cr6 的24h,48h和72hLC50分别为31.974,7.499和3.808mg/L;Cu2 ,Zn2 ,Cd2 和Cr6 对刺参幼参的安全浓度分别为0.018,0.362,0.259和0.750mg/L。四种重金属对刺参幼参的毒性大小依次为Cu2 >Cd2 >Zn2 >Cr6 。 相似文献
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根据潮流能水轮机的工作条件与技术要求,开发新型潮流能水轮机叶片专用翼型。建立多目标优化模型,采用遗传算法进行寻优求解,得到最大相对厚度范围为12.6%～38.8%的五种新翼型,构成潮流能水轮机叶片专用翼型族系列。开发了水平轴潮流能水轮机设计软件,搭建潮流能水轮机叶片翼型数据库,通过在潮流能水轮机设计软件中调用叶片翼型数据,为潮流能水轮机叶片设计提供方便。 相似文献
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针对水平轴潮流能水轮机,对其进行了力学分析并运用CFD方法对其水动力性能进行了仿真计算。比较了定常计算与非定常计算结果的区别,运用定常计算(MRF)方法得到了表现水轮机性能的功率、扭矩和推力特性曲线,分析了水轮机在不同尖速比时的表现。对水轮机模型进行了拖曳水池试验,并与仿真数据进行了比对分析,两者吻合度较好,并分析了试验过程中出现的在尖速比较大时功率系数衰减的现象,表明CFD方法对水轮机的工程实践有着指导意义。得到了尾流场的速度云图、流线分布图与衰减曲线,结果表明相对于水轮机的直径,受到其影响后的流场存在扩张现象。分析了水轮机后不同位置处的流场衰减情况,结果显示,随着水轮机后轴向距离的不同其速度恢复差别很大,对于今后潮流能水轮机的大规模布置方式研究提供了依据。 相似文献
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我国具有丰富的潮流能资源,但是存在潮流流速偏低、难以高效利用等问题。潮流能水轮机变桨距技术的利用,可有效提高潮流能资源利用效率。以提高潮流能水轮机高效获能为目标,分析了水轮机叶片桨距角对潮流能水轮机获能的影响规律,研究了水轮机变桨距技术原理及控制策略。在20 k W潮流能水轮机中运用了电动变桨距技术,根据潮流流速的不同,使用最大功率点追踪控制算法控制桨距角,并对机组运行过程进行实时测试。机组运行数据表明,与非变桨水轮机相比,变桨式潮流能水轮机可有效提高其获能效率。 相似文献
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为了研究潮流能水轮机尾流场的变化规律,本文在水平轴水轮机现有理论基础上,采用计算流体力学技术建立了数值模型,计算了水轮机的功率特性,进行了网格独立性验证,比较了模型中旋转区域不同对结果的影响。仿真结果与试验结果进行了对比分析,验证了数值模型的有效性。研究了全工况下尾流场速度衰减随尖速比和距离变化的规律,结果显示在小尖速比下尾流场速度恢复情况相对大尖速比下较好;靠近水轮机轮毂中心线位置处,衰减相对较大。研究建议水轮机在同等功率表现下尽量选择在小尖速比下工作,水轮机组在实际排列时避免采用成列布置,水轮机设计阶段应综合考虑功率特性和尾流场衰减。本文研究内容可以为潮流能水轮机的研究以及阵列式应用提供参考。 相似文献
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核果螺属(Drupa)和小核果螺属(Drupella),隶属于骨螺科(Muricidae)、红螺亚科(Rapaninae)。它们为暖水性较强的热带种类,主要分布于南中国海(海南岛以南),栖息于潮间带至浅海珊瑚礁或岩礁质环境中。对中国科学院海洋生物标本馆收藏的骨螺科标本进行了整理分类,共鉴定出2属,7种。并对以往使用混乱的种名进行了修订。 相似文献
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Tidal current energy is prominent and renewable. Great progress has been made in the exploitation technology of tidal current energy all over the world in recent years, and the large scale device has become the trend of tidal current turbine (TCT) for its economies. Instead of the similarity to the wind turbine, the tidal turbine has the characteristics of high hydrodynamic efficiency, big thrust, reliable sealing system, tight power transmission structure, etc. In this paper, a 1/5th scale horizontal axis tidal current turbine has been designed, manufactured and tested before the full scale device design. Firstly, the three-blade horizontal axis rotor was designed based on traditional blade element momentum theory and its hydrodynamic performance was predicted in numerical model. Then the power train system and stand-alone electrical control unit of tidal current turbine, whose performances were accessed through the bench test carried out in workshop, were designed and presented. Finally, offshore tests were carried out and the power performance of the rotor was obtained and compared with the published literatures, and the results showed that the power coefficient was satisfactory, which agrees with the theoretical predictions. 相似文献
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Tidal current power is one of the promising and reliable renewable energies with the advantage of continuous and predictable resource. It can make stable electricity regardless of weather conditions or seasons all year around. The required technologies for tidal current power in the ocean have been developed for years and now recognized that it could be commercialized after intensive field tests and successful demonstrations. There are several tidal farm development projects in the world, such as the MeyGen project in UK with its commercialization at hand. However, various research subjects in the tidal current energy field are seeking improvements and industrialization of tidal current power in terms of economy and technical reliability. This paper introduces the resource assessment procedure of tidal energy that has been applied in Korea coastal regions. The key research subjects for tidal current power together with the interaction effect of multi-arrangement is described. Also, this paper is to introduce the research output of each subject such as turbine design, experimental validation, turbine interaction and wake, multi-array module, FSI (fluid-structure interaction), and duct application. 相似文献
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潮流能发电装置支撑结构对水轮机水动力学性能影响研究 总被引：1，自引：0，他引：1
水平轴潮流能水轮机在工作过程中,由于支撑结构的存在,会使水轮机周围流场中的潮流流向、流速等参数发生不同程度的改变,进而影响水轮机的性能和发电装置的稳定性。为了研究支撑结构对水轮机水动力学性能的影响规律,以某100 k W单立柱座底式潮流能发电装置的支撑结构为研究对象,采用CFD方法,分别在正、反向来流时采用不同支撑结构的共六种工况下,对潮流能水轮机模型的获能和受力进行数值模拟。通过水槽模型试验,验证数值模拟的可靠性。研究结果表明:支撑结构对水轮机的水动力学性能的影响不容忽视,针对所研究的支撑结构,在正向来流时水轮机的获能系数降幅约30%,轴向力系数降幅约28%;反向来流时的降幅更大,分别约为63%和41%。 相似文献
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We recently showed the advantage of using a numerical system to extract energy from tidal currents by developing a new twin-turbine model (Li and Calisal, 2010a). Encouraged by this result, we decided to use this model to study another important characteristic of the turbine system, torque fluctuation. This effort is summarized in this paper. The torque fluctuation is expected to reduce the fatigue life of tidal current turbines, though potentially it also may deteriorate the power quality of tidal current turbines. In this paper, after reviewing the twin-turbine model, we use it to predict the torque fluctuation of the system with the same configurations as we used to study the power output in Li and Calisal (2010a). Specifically, we investigate the torque fluctuation of twin-turbine systems with various turbine parameters (e.g., relative distance between two turbines and incoming flow angle) and operational condition (e.g., tip speed ratio). The results suggest that the torque of an optimally configured twin-turbine system fluctuates much less than that of the corresponding stand-alone turbine, under the same operating conditions. We then extensively compare the hydrodynamic interaction’s impact on the torque fluctuation and the power output of the system. We conclude that the hydrodynamic interactions pose more constructive impacts on the torque fluctuation than on the power output. The findings indicate that the optimally configured counter-rotating system should be a side-by-side system, and that the optimally configured co-rotating system should have the downstream turbine partially in the wake of the upstream turbine depending on the detailed configuration of the turbines. Furthermore, one must balance the optimal torque fluctuation against the optimal power output. 相似文献
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近年来,潮流能能量转换技术发展迅速,但大型潮流发电机组基础结构方面的研究和应用还并不多见。针对潮流能电站基础结构在抗弯抗剪强度、桩径尺寸方面的特殊要求,结合我国潮流能富集区海底多为浅覆盖层或裸露基岩、且地形复杂的情况,提出了一种新型模块式嵌岩灌注桩基础结构。该基础结构的嵌岩灌注桩通过在桩内布置环形钢板箍和钢筋束来增强抗剪抗弯能力,使其在常规桩径即可满足潮流能电站的支撑要求,减少了对发电水流断面的阻挡;各主体灌注桩可通过横撑、纵撑和斜撑连接构成模块式基础,以适应不同地形条件、不同机组数量和安装方式的要求。新型模块式嵌岩灌注桩基础结构在LHD联合动能公司3.4 MV潮流发电项目中进行了首次应用,获得了良好的使用反馈。 相似文献
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潮流发电帆翼式柔性叶片水轮机实验研究 总被引：5，自引：0，他引：5
潮流发电水轮机是海洋潮流能发电系统的核心组成部分.帆翼式柔性叶片水轮机是一种全新水流发电装置,叶片由柔性材料制成,在流体力作用下自动调节攻角,能充分利用流体的升力和阻力效应做功.以帆翼式柔性叶片水轮机获能系数为研究目标,采用因次分析法初步分析可能影响获能系数的因素,通过模型实验对叶片弧弦比、叶片边弦比、叶片密度与获能系数的关系进行研究.不同结构形式转子存在不同叶片弧弦比最佳值,叶片边弦比愈大,获能能力愈强;在一定范围内,叶片密度较小时,获能与起转能力强,转速波动性较大,适用于低流速工况;反之获能与起转能力弱,稳定性较好,电能质量较高,适用于高流速工况.最后提出优化方案,实验证实优化后水轮机在获能能力和发电能力上均有所提高. 相似文献
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《Marine Policy》2017
Next generation turbines can be installed to exploit tidal energy resource in estuaries. However, the ecological implications of such deployments remain unknown. Accordingly, this study is focused on the impact of tidal farms on intertidal areas and associated waterbird habitats in estuaries. A numerical model simulates the hydrodynamic conditions of the Solway Firth, comprising one of the most extensive intertidal zones in the UK. The effects of tidal farms with different turbine densities have been evaluated in terms of changes to the areas of habitat for wetland bird species of conservation importance. The results suggest that any habitat loss may be minor and that in some cases there may be an increase (also small) in the area of important habitat. The percentage change in intertidal areas is also considerably lower than that expected to result from tidal barrages of similar capacities, implying the potential for tidal farms to present an alternative solution for exploiting tidal energy in highly protected areas. The changes in the extent of intertidal habitat are not proportional to the energy dissipated by the tidal farm. Therefore a range of tidal farm designs should be evaluated in order to optimise installed capacity while minimising habitat loss. However, the site-dependency of the impacts and the complex responses to change of estuarine ecosystems reinforce the requirement for detailed studies to be undertaken for each specific location and array configuration. The methodology presented here is appropriate for such assessments as it can be applied to different locations and turbine types. 相似文献
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一种新型鲸鱼式潮流能发电装置的设计与试验研究 总被引：1，自引：0，他引：1
为了进一步提高潮流能的利用率,提出了一种新型鲸鱼式潮流能发电装置。借鉴风机叶片设计方法及水平轴水轮机的设计原理,利用结构力学、流体力学和CFD相关方法,对该装置的螺旋桨叶、导流筒和固定桩等部件进行了设计研究,从获能效果、装置可靠性和发电功率等方面进行了优化设计,并通过900 W样机试验验证了设计的有效性。试验结果显示,海流高潮期装置最大发电功率可达到980 W,一天内大约有4个缓潮期,此间发电功率明显下降,但持续时间不长,总体平均发电功率在800 W上下;同时潮流能轮机启动流速在0.41 m/s左右,有着良好的低速启动性能。 相似文献
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考虑发电机尾流作用的潮流能理论可开发量的评估 总被引：1，自引：1，他引：0
In this study, we construct one 2–dimensional tidal simulation, using an unstructured Finite Volume Coastal Ocean Model(FVCOM). In the 2–D model, we simulated the tidal turbines through adding additional bottom drag in the element where the tidal turbines reside. The additional bottom drag was calculated from the relationship of the bottom friction dissipation and the rated rotor efficiency of the tidal energy turbine. This study analyzed the effect of the tidal energy turbine to the hydrodynamic environment, and calculated the amount of the extractable tidal energy resource at the Guishan Hangmen Channel, considering the rotor wake effect. 相似文献