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1.
振荡水柱式(Oscillation Water Column,简称OWC)波浪能采集装置具有结构简单、稳定性好、海洋环境适应性强等优点。为了提高该装置波能采集效率,研究波浪进入气室的振荡水柱气动特性与装置结构参数关系,为系统设计提供理论基础。以振荡水柱式波能转换理论计算分析为基础,采用Simulink软件分别建立前墙处入口压强Pq求解模型、装置气室内压强Po求解模型以及装置内振荡水柱运动方程y求解模型,研究目的是综合分析振荡水柱气室内压强与气室结构、波浪流体动力学参数之间的变化关系。  相似文献   

2.
振荡水柱(Oscillating water column,OWC)波浪能采集装置气室底部引浪通道对波浪能采集效率具有重要意义。基于流体动力学分析(CFD)技术研究OWC装置气室底部轮廓的优化问题,在ICEM CFD仿真分析系统中建立4种气室底部结构的二维引浪通道模型,应用FLUENT软件流体分相处理及明渠造波法和数值沙滩消波方法建立基于线性波浪理论的二维数值波浪水槽。仿真分析显示,圆形底部轮廓OWC气室较其它3种轮廓结构的气室墙壁受到压力小,形成的反射波小,波能损失小,气室出口速度快由此形成的气室压力大,波能转换效率高。  相似文献   

3.
采用计算流体动力学分析(CFD)技术研究离岸式振荡水柱波能转换装置的设计参数优化问题。首先,借助FLUENT软件用户自定义函数功能(UDF)并运用动边界造波及多孔介质消波方法建立基于线性波浪理论的二维数值波浪水槽,然后,将水槽的分析方法应用于振荡水柱气室仿真研究。结果表明:离岸式振荡水柱气室在发生共振时转换效率最高,气室内液面升降幅度随着波能转换装置的前墙入水深度、厚度以及气室宽度的减小而产生较明显的增大;相对于前墙尺寸,气室宽度对波能转换装置的能量转换功率影响较大。  相似文献   

4.
振荡水柱装置是目前世界上应用最为广泛的岸式波能发电装置.气室作为该装置的主要结构可将入射波浪的能量转换为往复振荡的气流动能,是完成能量一次转换的关键结构.为了建立用于考察入射波浪、气室内的波面振荡变化,准确预测气室工作性能的三维数值模拟模型,构建了基于VOF模型的三维数值波浪水槽.通过与物理模型试验的结果对比发现,该模...  相似文献   

5.
振荡水柱式波能发电系统中波能转换主要结构气室能将入射波能转换为往复振荡的空气动能从而实现能量一次转换,该过程的气室压强研究对发电系统设计具有重要意义。因此针对"引浪板"和"引浪通道"的三维侧向开口固定式振荡水柱波能转换系统,采用三维Green函数法建立了气室内水气动力学性能的压缩空气压强理论计算模型。计算时为了满足压强与速度连续条件,响应脉动源与扰动脉动源两者在交界面上需要相互匹配;同时为了能够精确快速地求解三维Green函数,采用了多维切比雪夫(Chebyshev)多项式和渐近展开式快速近似计算方法。计算结果表明所用方法简单可靠,同时计算结果可应用于振荡水柱波能发电系统性能预测及相关问题研究。  相似文献   

6.
为解决海洋监测微型传感器供能问题,设计新型波浪能捕获装置,在海面振荡浮筒气室产生空气气柱,驱动介电弹性体形变发电为传感器供能。建立振荡浮子式气柱数值模型,研究新型振荡水柱发电计算理论。利用水动力仿真软件AQWA求解浮子所受波浪力作用振荡幅值、辐射阻尼和附加质量。基于Simulink软件分别计算波浪作用下浮子位移和气室内水柱位移,根据两者的位移差计算气室体积变化所产生的空气压强、介电弹性体发电薄膜形变量和系统输出电能,单次循环周期最大发电量达到24.6 mJ。分析波浪周期、发电薄膜几何参数等对输出电能的影响。  相似文献   

7.
振荡水柱(Oscillation Water Column,OWC)是近年来发展较快的波浪能采集技术,该装置主要由箱体、振荡水柱和压缩空气柱组成,而波浪在气室内产生的压强对能量转换效率等起到决定作用。结合三维侧向开口的振荡水柱波能转换装置,基于线性波理论,采用三维Green函数法建立了气室内水气动力学性能的空气压强理论计算模型,利用多维切比雪夫(Chebyshev)多项式求解,计算结果精度高,能够准确表达波浪和结构设计参数对气室内压强影响。依据理论计算模型分析了波浪周期、波长、吃水深度、入射波幅等参数对气室内压强作用。  相似文献   

8.
基于VOF模型的OWC气室波浪场数值分析   总被引:1,自引:0,他引:1  
近年来,振荡水柱形式在波能转换装置中得到了广泛应用,由于波况不同,需对气室加以研究并对其形状参量进行优化,从而使空气流速和能量转换达到最大值.利用基于VOF模型建立二维数值波浪水槽,将数值计算的振荡水柱在气室内的升沉运动与物理模型试验进行比较,验证其正确性,并将OWC气室的研究手段予以推广.  相似文献   

9.
波浪能发电装置的波能转换通常分为两级能量转换:第一级能量转换是波浪作用下波浪能装置部件发生相对运动驱动PTO做功捕获波浪能;第二级能量转换为将捕获的波浪能转换为电能。其中一级波浪能转换系统的优化设计是提高波浪能装置能量转换效率的重要手段和关键技术。波浪作用下波浪能装置的运动与PTO做功运动相互耦合和影响,本文通过对不同波浪要素环境下、不同PTO阻尼下波浪能装置的频域运动模拟,以迎波宽度比为尺度对波浪能装置的一级能量转换系统进行优化设计,获得波浪能装置的最优做功阻尼,为实型装置负载加载设计提供设计依据,提高波浪能装置能量转化效率。鹰式一号波浪能装置的实海况运动证明,通过对一级能量转换系统的优化设计,能够有效提高装置的发电效率和提高装置对波浪响应频带宽度。  相似文献   

10.
为实现建造、运行和维护等方面的资源共享,将振荡水柱(oscillating water column,简称OWC)波能转换装置与现有海工结构集成耦合,已成为目前海洋波浪能转换利用的热点问题。以集成于方箱防波堤的双气室OWC装置为研究对象,借助开源代码平台OpenFOAM和造/消波工具箱waves2Foam,采用流体体积法(VOF)捕捉自由面和6自由度(6DOF)动网格求解器模拟垂荡运动响应,对在不同规则波作用下,中墙相对宽度、中墙相对吃水对装置波能转换效率及水动力特性的影响进行数值研究。结果表明,较大的中墙相对宽度能够增强装置的波能转换效率(ξtotal(max)=73%)、降低结构物的相对垂荡位移并对装置前后气室内水柱的振荡幅度与压强变化产生影响;增加中墙相对吃水能显著提高气室在中高频波段波能提取效率(ξtotal(max)=78%),并显著拓宽气室的高效频率带宽(0.9≤ω2h/g≤2.2)。  相似文献   

11.
The motion and the drift force of a floating OWC (oscillating water column) wave energy device in regular waves are studied taking account of the oscillating surface-pressure due to the pressure drop across the duct of the air chamber. The potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine-type Green function while the outer problem with the Kelvin-type Green function. The added mass, wave damping and excitation coefficients as well as the motion and drift force of the OWC device are calculated for various values of parameter related to the pressure drop.  相似文献   

12.
A pile-supported OWC breakwater is a novel marine structure in which an oscillating water column (OWC) is integrated into a pile-supported breakwater, with a dual function: generating carbon-free energy and providing shelter for port activities by limiting wave transmission. In this work we investigate the hydrodynamics of this novel structure by means of an analytical model based on linear wave theory and matched eigenfunction expansion method. A local increase in the back-wall draft is adopted as an effective strategy to enhance wave power extraction and reduce wave transmission. The effects of chamber breadth, wall draft and air chamber volume on the hydrodynamic performance are examined in detail. We find that optimizing power take-off (PTO) damping for maximum power leads to both satisfactory power extraction and wave transmission, whereas optimizing for minimum wave transmission penalizes power extraction excessively; the former is, therefore, preferable. An appropriate large enough air chamber volume can enhance the bandwidth of high extraction efficiency through the air compressibility effect, with minimum repercussions for wave transmission. Meanwhile, the air chamber volume is found to be not large enough for the air compressibility effect to be relevant at engineering scales. Finally, a two-level practical optimization strategy on PTO damping is adopted. We prove that this strategy yields similar wave power extraction and wave transmission as the ideal optimization approach.  相似文献   

13.
This paper presents the test of a ship model for the design of a backward-bent duct oscillating water column type wave energy conversion system, to supply electric power for a light ship. This system suggests a new way to produce electric power automatically for large light ships.  相似文献   

14.
振荡水柱波能转换装置的最大转换效率往往受到腔内水柱共振机制的直接影响。通过对装置的基本结构进行简化,提出了一种前墙可绕固定轴旋转的双垂板式结构系统,旨在通过前墙的旋转运动进一步加剧水柱的振荡,从而对腔内水柱的共振机制进行调节和控制。基于线性波理论,采用匹配特征函数展开法对波浪与双垂板结构的相互作用进行理论研究,针对流场在结构物尖角附近的奇异性特征,将公共界面上的速度分布基于切比雪夫多项式近似展开,并应用区域间的速度与压力连续条件进行求解。通过分析结构的几何参数对反射透射系数、平均波面高程、前墙旋转振幅以及前墙与水面间相位差的影响,深究其共振机理,为振荡水柱波能转换装置的效率优化机制提供理论依据。结果表明,在所研究的波浪频率范围内,前墙的自由旋转运动会加剧板间的平均波面高程,应用于波浪能转换装置中能进一步拓宽高效频率带宽。  相似文献   

15.
The paper presents a concept of a wave energy converter and the numerical model to calculate the hydrodynamic responses in waves and the power produced by the power take off system. The system consists of an asymmetric floater with an interior U-tank partially filled with water and two lateral air chambers connected by a duct. The motion of the U-shaped oscillating water column, mainly induced by the rolling of the floater, forces the air through the duct where a Wells turbine is installed to absorb the wave energy.The wave-floater hydrodynamics is calculated with a Green's function panel method, while the oscillating water column motions hydro-mechanics are derived from the one-dimensional Euler's equation. The dynamics of the Wells turbine is realistically represented by one additional differential equation on the unknown air pressure fluctuation. This equation is derived assuming small amplitude motions of the water column and assuming the linear isentropic relation is valid for the air thermodynamics in the air chambers. The Wells turbine is characterized by a drastic drop of efficiency above a critical pressure value due to stalling on the blades. The effect of a by-pass valve to prevent stalling is introduced in the numerical model in a simplistic way. The numerical model is implemented and tested for a wave energy converter with a displacement of 1150 t, including 490 t for the interior water column, and an installed turbine with 2.3 m of diameter. An analysis of the influence of changing different design parameters on the system efficiency is also presented.  相似文献   

16.
杨鑫  刘臻  张晓霞 《海洋工程》2021,39(5):78-85
径流式空气透平是振荡水柱式波能发电系统的二级能量转换装置,因其具有结构简单、输出扭矩大、轴向推力小的优势,得到了越来越多的关注。采用计算流体力学软件Ansys-Fluent 12.0,通过数值模拟方法考察了不同转子叶片稠度对径流式空气透平定常无量纲评价参数的影响规律。研究结果表明:虽然径流式透平可在双向气流下实现单向旋转,但当气流通过方向不同时,透平的定常工作性能存在明显差异,这与传统轴流式透平完全不同;此外,稠度对透平效率的影响在不同流量系数范围内也不同。因此,综合考虑气流流向、透平整个工作范围内输出效率,推荐采用的转子叶片稠度为2.34。  相似文献   

17.
A structure scheme of a pile-based breakwater with integrated oscillating water column(OWC) energy conversion chamber was proposed, and four structure forms had been designed. Based on the physical test, the variations of the reflected wave height, the transmitted wave height, the air velocity at the outlet of the chamber, the air pressure and the wave height in the air chamber were studied under the conditions of different wave heights, periods, with or without elliptical front wall and the baffles on both sides of the chamber. Moreover, based on the results, the changes and relationship between the wave-eliminating effect and energy conversion effect of the scheme were analyzed. In general, it turns out, the transmission coefficients of the four structure forms are kept below 0.5. Furthermore, the transmission coefficients of the structural forms G2, G3, and G4 were all smaller than 0.4, and it is only 0.1 at its smallest. Thereinto, in general, the structure form G4 has the best wave-eliminating and energy conversion performance. At the same time, when the wave steepness is 0.066, the energy conversion and wave dissipation effect of the four structure forms is the best. The research results could be provided as the reference for the design structure selection of pile-based breakwater with integrated OWC energy conversion chamber.  相似文献   

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