|Table of Contents|

Study on wind tunnel test of urban wind environment under thermal effects(PDF)

《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]

Issue:
2023年01期
Page:
103-111
Research Field:
建筑结构
Publishing date:

Info

Title:
Study on wind tunnel test of urban wind environment under thermal effects
Author(s):
YANG Ying1;  HU Jiayi1;  SHEN Lian1; 2;  WANG Kuo1;  SUN Yu3;  XU Chishi3
(1. Hunan Province Research Center for Safety Control Technology and Equipment of Bridge Engineering, Changsha University of Science & Technology, Changsha 410076, Hunan, China; 2. School of Civil Engineering, Changsha University, Changsha 410012, Hunan, China; 3. Hunan Architectural Design Institute Group Co., Ltd, Changsha 410208, Hunan, China)
Keywords:
Richardson number;  wind tunnel test;  wind field analysis;  thermal effect;  wind environment
PACS:
TU119
DOI:
10.19815/j.jace.2021.07043
Abstract:
Temperature is one of the main factors affecting the comfort of the city, the mechanism of the flow field is not clear so far. In order to reveal the influence of temperature field on the flow field, based on the large-scale wind tunnel, the average wind under different thermal conditions was tested and studied. The wind speed at pedestrian height, the along-wind speed of relevant measuring points and the distribution of Reynolds shear stress under different Richardson numbers Rb were obtained and analyzed in detail. Taking a residential district in Changsha as the research background, the distribution law of wind field at pedestrian height under different thermal effects was explored, the correlation coefficient of typical measuring points under thermal conditions was obtained, and the wind environment at pedestrian height under thermal effects was quantitatively evaluated by the method of exceedance probability. The results show that in the range of -0.38<Rb<0, the flow field of the empty wind tunnel increases with the thermal effect, and the near-surface wind speed increases relatively large, and the increase gradually slows down with the increase of height. In practice, the wind environment of pedestrian height in the community is less affected by temperature as a whole. The main influence is concentrated below the wind speed ratio of 0.6, and the maximum root mean square is 0.635. When the wind speed ratio is above 0.6, the effect of temperature on wind speed is relatively small. The thermal effect has little influence on the correlation and comfort degree of pedestrian height wind field, and the maximum influence values are only 8% and 3.87%.

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Last Update: 2023-01-01