隔声屏障对街道峡谷污染物扩散的影响

发布时间：2018-05-26 08:33

本文选题：隔声屏障 + 街道峡谷　；参考：《环境工程》2016年10期

【摘要】：对带有隔声屏障的街道峡谷内流场和污染物浓度场进行了数值模拟,探讨了风速、隔声屏障高度及与建筑物间的距离对流场及污染物扩散的影响。模拟结果显示:街谷内由1个稳定的主涡及街角两侧隔声屏障所在区域的3个附属涡组成。隔声屏障改变了街谷底部的流型,提高了街谷内的x、y方向速度峰值,但在隔声屏障附近区域x方向速度场明显减弱,这也是污染物聚集原因之一。与无隔声屏障相比,隔声屏障的存在物理性阻隔了污染物扩散路径,提高了街道峡谷内污染物浓度峰值,其中行人高度处背风面污染物浓度升高27.51%~28.72%,迎风面污染物浓度升高11.64%~19.99%。街谷内污染物浓度的分布和峰值由风场、隔声屏障高度及与建筑物之间的距离共同决定。
[Abstract]:The flow field and pollutant concentration field in street canyons with noise barrier are numerically simulated. The effects of wind speed, the height of noise barrier, the distance between the barrier and the building and the dispersion of pollutants are discussed. The simulation results show that the valley consists of a stable main vortex and three secondary vortices in the area of the noise barrier on both sides of the street corner. The noise barrier changes the flow pattern at the bottom of the valley and increases the peak value of the xy direction velocity in the valley, but the velocity field in the x direction is obviously weakened near the barrier, which is one of the reasons for the accumulation of pollutants. Compared with the non-noise barrier, the existence of the barrier physically blocked the pollutant diffusion path and increased the peak concentration of pollutants in the street canyon. The concentration of pollutants in the leeward surface of pedestrian height increased 27.51% and 28.72%, and the concentration of pollutants on the upwind surface increased 11.64% 19.99%. The distribution and peak value of pollutant concentration in the valley are determined by wind field, the height of noise barrier and the distance between the building and the noise barrier.
【作者单位】：西安交通大学人居与建筑工程学院;西南交通大学土木工程学院;
【基金】：国家自然科学基金(21306145) 国家重大科技专项(2016ZX05011001-002)
【分类号】：TB53

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