The Study Of Pedestrian Level Wind Environment Around Typical High-rise Building Based On Different Approaching Wind Characteristics

In recently years,the rapid development of China's economy and society has brought great opportunities for the development of high rise buildings.Meanwhile,pollutant dispersion in urban areas has become another issue of public concern,particularly in those densely populated cities.The research on evaluating of building wind environment become more and more important.The impact of building surface temperature rise caused by solar radiation on the air flow near buildings and the cross contamination in context of dense buildings cannot be overlooked,but few studies have been carried out on such impact.This paper focus on the characteristics of pedestrian level wind environment and the cross-contamination when temperature rise.Base on previous studies,this paper firstly introduces the evaluation methods of building wind environment and relevant theoretical knowledge of CFD numerical simulation.Then,the reliability of the numerical simulation method is demonstrated through the comparisons with previous wind tunnel experiment.The flow field characteristics around 2 typical high-rise building types including 6 different building shapes are investigated.Then average wind ratio is employed to reveal the flow characteristics under different wind directions.After that,the re-circulation flow region lengths under different temperature rising on the ground surface are compared to study the impact of ground heating on the wind environment.Then,based on frequently used internal partitions in offices,the influence of different supply and return air mixed and pollutant source distributions on the flow field and diffusion performance with an internal partition.Lastly,a model of typical high-rise building is created.The normalized concentration Kc is used as an indicator to evaluate the dispersion characteristics under different source locations without surface temperature rise.Together with the wake zone vortex core position,the effect of wall surface rise on the cross contamination and flow fields near wall are respectively evaluated.