摘要
【目的】针对风电工程中风电机组频发的净空减少现象,分析了负切变形成的影响因素,主要为大气热稳定度、地面粗糙度和地形因素。【方法】根据选址需要,以复杂地形条件下风切变特性为研究对象,以某复杂地形风电场测风塔和机位实测数据为基础,利用计算流体力学(computation fluid dynamics,CFD)方法,通过稳态模拟和瞬态模拟分析峡谷地形条件下不同位置处的风切变,对风资源进行精细化评估。【结果】研究表明,进行风资源精细化评估时,需要对峡谷地形分扇区进行风切变分析,避免整体为正切变而忽略局部扇区为负切变的情形;稳态结合瞬态模拟可获得阵风条件下各机位风切变特性。正午时测风塔实测平均风切变为-0.01,迎风坡山脊线上机位F07的叶轮面处于负切变区域;0时刻,叶轮面风切变为-0.009,2/8T(T为研究周期)时刻,35 m高度处风速达到18.55 m/s,165 m高度处风速为16.76 m/s,二者风速差为1.79 m/s,叶轮面风切变值为-0.066,地形因素导致该机位负切变增大。【结论】建议机位可选址在低于峡谷山脊的迎风坡处,选择不同的机型或同一机型不同轮毂高度来调整叶尖与地面的距离,避开或减轻负切变的影响;考虑到山体遮挡导致的回流影响,不应将机位布置在峡谷两侧和背风坡侧;对已建项目应采用叶片净空优化设计、叶片净空监测等技术措施,防止叶片与塔筒发生碰撞的风险。
[Objective]In view of the frequent clearance reduction of wind turbines in wind power projects,the causes of negative shear are analyzed,mainly including atmospheric thermal stability,ground roughness and terrain factors.[Methods]According to the needs of site selection,the wind shear characteristics under complex terrain conditions are taken as the research object.Based on the measured data of the wind tower and the position of a wind farm in a complex terrain,the wind shear at different positions under canyon terrain conditions is analyzed by steady-state simulation and transient simulation using the computational fluid dynamics(CFD)method,and the wind resources are evaluated in detail.[Results]The simulation results show that it is necessary to analyze the wind shear of the canyon terrain in different sectors when evaluating the wind resources,so as to avoid the situation that the whole is positive shear and the local sector is negative shear.The steady-state simulation combined with transient simulation can obtain the wind shear characteristics of each position under gust conditions.At noon,the measured average wind shear of the wind tower is-0.01,and the position on the ridge line of the windward slope is F07,and the impeller surface is in the negative shear area.0,the wind shear on the impeller surface becomes-0.009,2/8T,the wind speed at 35 m height reaches 18.55 m/s,the wind speed at 165 m height is 16.76 m/s,the wind speed difference between the two is 1.79 m/s,the wind shear on the impeller surface is-0.066,and the topographic factors lead to the increase of the negative shear of the position.The position can be located on the windward slope below the canyon ridge.[Conclusion]It is recommended to select different models or different hub heights of the same model to adjust the distance between the tip and the ground to avoid or reduce the impact of negative shear.Considering the influence of the backflow caused by the occlusion of the mountain,the seats should not be arranged on both sides of the canyon and the leeward slope;technical measures such as blade clearance optimization design and blade clearance monitoring should be adopted for existing projects to prevent the risk of collision between blades and tower.
作者
王莹
袁飞
夏德喜
WANG Ying;YUAN Fei;XIA Dexi(China Energy United Power Technology Co.Ltd.,Beijing 100039,China)
出处
《电力科技与环保》
2025年第4期658-667,共10页
Electric Power Technology and Environmental Protection
基金
国家能源集团联合动力技术有限公司北京技术开发分公司科技项目(JSKF-2022-01)。
关键词
风电机组
CFD
负切变
峡谷地形
wind turbines
CFD
negative wind shear
canyon terrain
