为研究下击暴流水平风速的竖向相关性，采用冲击射流装置模拟了稳态下击暴流风场，测量了不同径向位置、竖向距离、地貌条件以及射流速度下的水平风速，重点分析了水平风速的竖向相关性和相干曲线，提出了稳态下击暴流风场的相干函数模型。结果表明：相关系数随径向距离的增加而先增大后减小，最大相关系数出现在r=1.0Djet附近，地面粗糙度和射流风速对相关系数影响较小。相干函数与测点的竖向间距密切相关，径向位置和射流风速对相干函数影响较小，地表粗糙度的增加会降低近地测点对的相干性。基于试验数据，建立了稳态下击暴流竖向相干函数模型，实现了与试验风场的较好吻合。
Abstract
In order to study the vertical coherence of the horizontal wind speed of downburst, the steady downburst wind field was simulated using an impinging jet device, and the horizontal wind speed under different radial positions, vertical distances, terrain conditions and jet velocities was measured. The vertical correlation and coherence curve of the horizontal wind speed were emphatically analyzed, and the coherence function model of the steady downburst wind field was proposed. The results show that the correlation coefficient first increases and then decreases with the increase of the radial distance, and the maximum correlation coefficient appears near r=1.0Djet, and the ground roughness and jet wind speed have little influence on the correlation coefficient. The coherence function is closely related to the vertical spacing of the measuring points, the radial position and jet wind speed have little influence on the coherence function, and the increase of the surface roughness will reduce the coherence of the near-earth measuring point pair. Based on the test data, the vertical coherence function model of the steady-state downburst is established, which is in good agreement with the experimental wind field.
关键词
下击暴流 /
冲击射流 /
水平风速 /
相关系数 /
相干函数
{{custom_keyword}} /
Key words
downburst /
impinging jet /
horizontal wind speed /
correlation coefficient /
coherence function
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] Solari G. Emerging issues and new frameworks for wind loading on structures in mixed climates[J]. Wind Struct, 2014, 19 (3): 295-320.
[2] Lombardo F T, Smith D A, Schroeder J L, Mehta K C. Thunderstorm characteristics of importance to wind engineering[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2014, 125: 121-132.
[3] Shehata A, El Damatty A: Assessment of the failure of an electrical transmission line due to a downburst event, Electrical Transmission Line and Substation Structures: Structural Reliability in a Changing World, 2007: 27-38.
[4] 李春祥,李锦华,于志强.输电塔线体系抗风设计理论与发展[J].振动与冲击,2009,28(10):15-25+222-223.
LI Chunxiang, LI Jinhua, YU Zhiqiang. A review of wind-resistant design theories of transmission tower-line systems[J]. Journal of Vibration and shock, 2009, 28(10):15-25+222-223.
[5] Huang G, Liu W, Zhou Q, et al. Numerical study for downburst wind and its load on high-rise building[J]. Wind & structures, 2018, 27(2): 89-100.
[6] Davenport A G. The spectrum of horizontal gustiness near the ground in high winds[J]. Quarterly Journal of the Royal Meteorological Society, 1961, 87(372): 194-211.
[7] Kristensen L, Panofsky H A, Smith S D. Lateral coherence of longitudinal wind components in strong winds[J]. Boundary-Layer Meteorology, 1981, 21: 199-205.
[8] 黄东梅,朱乐东,丁泉顺.大气边界层风速竖向相干函数实验研究[J].实验流体力学,2009,23(04):34-40.
HUANG Dongmei, ZHU Ledong, DING Quanshun. Experimental research on vertical coherence function of wind velocities in atmospheric boundary layer wind field [J]. Journal of Experiements in Fluid Mechanics, 2009, 23 (04) :34-40.
[9] 楼文娟,段志勇,张少锋等.湍流尺度内风场的水平向空间相关性研究[J].建筑结构学报,2016,37(01):77-84.
LOU Wenjuan, DUAN Zhiyong， ZHANG Shaofeng, et al.Experimental study on horizontal coherence of wind speed for separations comparable to turbulent scales [J]. Journal of Building Structures, 2016, 37(01): 77-84.
[10] Gunter W S, Schroeder J L. High-resolution full-scale measurements of thunderstorm outflow winds[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2015, 138: 13-26.
[11] Repetto M P, Burlando M, Solari G, De Gaetano P, Pizzo M. Integrated tools for improving the resilience of seaports under extreme wind events[J]. Sustainable cities and society, 2017, 32: 277-294.
[12] 刘慕广,胡家锴,余先锋等.下击暴流风特性及其对高耸桅杆动力作用的实测分析[J].建筑结构学报,2023,44(03):157-166.
LIU Muguang, HU Jiakai, YU Xianfeng, et al. Observational study of wind characteristics of thunderstorm and dynamic effects on high-rise masts [J]. Journal of Building Structures. 2023 ,44(03) :157-166.
[13] Zhang S, Yang Q, Solari G, Li B, Huang G. Characteristics of thunderstorm outflows in Beijing urban area[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2019, 195: 104011.
[14] Chen L, Letchford C W. Multi-scale correlation analyses of two lateral profiles of full-scale downburst wind speeds[J]. Journal of wind engineering and industrial aerodynamics, 2006, 94(9): 675-696.
[15] Holmes J D, Hangan H M, Schroeder J L, et al. A forensic study of the Lubbock-Reese downdraft of 2002[J]. Wind and structures, 2008, 11(2): 137-152.
[16] Zhang A, Zhang S, Xu X, et al. Variation Characteristics of the Wind Field in a Typical Thunderstorm Event in Beijing[J]. Applied Sciences, 2022, 12(23): 12036.
[17] Fujita T T. Tornadoes and downbursts in the context of generalized planetary scales[J]. Journal of Atmospheric Sciences, 1981, 38 (8): 1511-1534.
[18] Fujita T T. Downbursts: meteorological features and wind field characteristics[J]. Journal of wind engineering and industrial aerodynamics, 1990, 36: 75-86.
[19] Lettau, H. Note on Aerodynanic Roughness-Parameter Estiation on the Basis of Roughness-Element Description [J]. J. Appl. Meteorol.1969,8,828-832
[20] Hjelmfelt M R. Structure and life cycle of microburst outflows observed in Colorado[J]. Journal of Applied Meteorology and Climatology, 1988, 27 (8): 900-927.
[21] Chay M T, Letchford C W. Pressure distributions on a cube in a simulated thunderstorm downburst—Part A: stationary downburst observations[J]. Journal of wind engineering and industrial Aerodynamics, 2002, 90(7): 711-732.
[22] Wu Z, Iida Y, Uematsu Y. The flow fields generated by stationary and travelling downbursts and resultant wind load effects on transmission line structural system[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2021, 210: 104521.
[23] Letchford C W, Chay M T. Pressure distributions on a cube in a simulated thunderstorm downburst. Part B: moving downburst observations[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2002, 90(7): 733-753.
[24] 曾加东. 矩形高层建筑脉动风荷载空间相关性及结构风振响应研究[D].西南交通大学,2017.
ZENG Jiadong. Spatial Correlation of Fluctuating Wind Loads and Wind-Induced Response on Rectangular High-Rise Buildings[D]. Southwest Jiaotong University, 2017.
{{custom_fnGroup.title_cn}}
脚注
{{custom_fn.content}}
PDF(2046 KB)
