融合式叶尖结构变化对风力机叶尖区域流场及噪声场的影响研究  

RESEARCH ON EFFECT OF FUSION TIP STRUCTURE CHANGE ON FLOW FIELD AND NOISE FIELD IN TIP REGION OF WIND TURBINE

作　　者：吴伟民 姚建尧[1] 代元军 刘竟成[3] Wu Weimin;Yao Jianyao;Dai Yuanjun;Liu Jingcheng(College of Aerospace Engineering,Chongqing University,Chongqing 400044,China;School of Energy Engineering,Xinjiang Institute of Engineering,Urumqi 830091,China;School of Petroleum Engineering,Chongqing University of Science and Technology,Chongqing 401331,China)

机构地区：[1]重庆大学航空航天学院,重庆400044 [2]新疆工程学院能源工程学院,乌鲁木齐830091 [3]重庆科技学院石油与天然气工程学院,重庆401331

出　　处：《太阳能学报》2020年第12期190-198,共9页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(51466015);国家青年自然科学基金(11502037)。

摘　　要：针对模型尺寸风力机提出不同折角的融合叶尖结构形式,为了探索其叶尖区域流场和噪声场的影响,采用混合网格布局的CFD数值计算方法,利用LES模型和FW-H声学类比算法对不同尾迹中紧密相关的流场和噪声场的演化规律进行分析。结果表明:由于受到融合式叶尖结构的影响,叶尖涡的产生位置较原始设计叶轮条件下均明显向X轴负向移动,且叶尖涡影响的流场高梯度区域的范围呈逐渐缩小。又由于不同叶尖结构叶轮随折角的变化,造成叶尖涡向径向外移动,所对应的基频声压级值局部峰值位置也发生规律性外移。同时,具有融合式叶尖结构的叶轮的尾迹监测点处的基频声压级较原始叶轮对应声压级均有所降低,表明该融合式叶尖结构能影响叶尖涡的形成位置和强度,且具有一定的降噪性能。此外,因为该验证测试的风洞为非声学风洞,以及实测声压值是基于时域响应的平均值,而模型计算中采用尾迹流场对应的瞬态值,所以计算值和实验值偏差较大,但其呈现的频谱变化趋势一致,说明该研究能为设计高效低噪的小型水平轴风力机提供理论参考。A fusion tip structure with different angles is proposed for the model size wind turbine. In order to explore its influence on the flow field and noise field in the tip region,the LES model and the FW-H acoustic analogy algorithm are both used to analyze the evolution of flow and noise fields in the different wakes. The results indicate that,due to the influence of the fusion tip structure,the initial position of the tip vortex is significantly shifted to the negative direction of X axis,compared to the situation of original design impeller. Meanwhile,the range of the high gradient region of the flow field affected by the tip vortex gradually reduces. Because of the change of the folding angle of the impeller with different tip structure,the tip vortex moves outward radially,and the corresponding location of the peak value of the sound pressure level value of the fundamental frequency also shifts outward. At the same time,the baseband sound pressure level at the wake monitoring point of the impeller with the fusion tip structure is lower than the corresponding sound pressure level of the original impeller. Therefore,it demonstrates that such fusion tip structure can affect the formation position and strength of the tip vortex and it has certain noise reduction performance. The verification test is carried out using a non-acoustic wind tunnel. As the results, the trend of spectrum change is consistent although the calculated value and the experimental value has a large deviation. The reasons may be that the measured sound pressure value is based on the average of the time domain response,also the model calculation uses the transient value corresponding to the wake flow field. It indicates that the study can provide a theoretical reference for the design of small horizontal axis wind turbine with high efficiency and low noise.

关 键 词：风力机 叶尖涡 声压级 融合式叶尖结构 CFD数值模型 

分 类 号：TK83[动力工程及工程热物理—流体机械及工程]