湍流尺度内风场的水平向空间相关性研究  

Experimental study on horizontal coherence of wind speed for separations comparable to turbulent scales

作　　者：楼文娟[1] 段志勇[1] 张少锋[2] 卢明[2] 吕中宾[2] 

机构地区：[1]浙江大学结构工程研究所,浙江杭州310058 [2]国网河南省电力公司电力科学研究院国网输电线路舞动防治技术重点实验室,河南郑州450002

出　　处：《建筑结构学报》2016年第1期77-84,共8页Journal of Building Structures

基　　金：国家自然科学基金项目(51178424;51378468)

摘　　要：基于2 616 h的风场实测脉动风速数据,研究了风场的水平向风速空间相关函数,提出了湍流尺度内的相关函数模型。结果表明:空间相关性的强弱与风向角、空间间距和平均风速密切相关。对不同风向角、空间间距和平均风速的空间相关函数曲线进行最小二乘法非线性拟合,确定了各曲线的衰减指数,纵向衰减指数与纵向空间间距和平均风速之比的1/2次方成正比,横向衰减指数与横向空间间距平方和平均风速之比成正比。在此基础上,建立了纵向、横向和混合向空间相关函数模型,并与现有的模型进行了对比。在湍流尺度内,Davenport模型计算值明显高估于实际风场的水平空间相关函数值,Schlez模型和Irwin模型计算值均大于实际风场的横向空间相关函数值,而文中提出的模型计算值与实际风场的水平空间相关函数值吻合较好,能有效预测脉动风速的水平空间相关性。2 616 h long field measured fluctuating wind records were evaluated with respect to the horizontal coherence function. Based on these experimental data, a mathematical model was proposed to describe the coherence function, which was available for separations comparable to the turbulent scales. Results show that horizontal coherence is in close relation with wind direction angle, spatial distances and mean wind speed. Nonlinear fitting by the least square method was presented and subsequent decay indices were obtained. Then the relevance between horizontal coherence and different factors, including wind direction angles, spatial distances and mean wind speed was analyzed. The results show that the longitudinal decay indices are proportional to the square root of distance-speed ratio, while transverse decay indices are in direct proportion to the ratio of the squared distance to the mean wind speed. Then empirical models for longitudinal, transverse and hybrid coherence were established accordingly. Comparison was made with other coherence models. The results show that Davenport model overestimate horizontal coherence, so as the Schlez and Irwin model to transversal coherence, and the model proposed here is in good agreement with the measured coherence, which can properly describe the horizontal coherence of turbulent wind speed.

关 键 词：风场 风向角 空间间距 平均风速 现场实测 水平空间相关性 

分 类 号：TU312.1[建筑科学—结构工程] TU317.2