高路堤及涵洞建造对居住环境流场的影响

Influence of High Embankment and Culvert on Flow Fieldof Living Environment

高路堤涵洞是道路交通的重要组成部分,但是高路堤涵洞的建设往往会对周围环境的流场造成一定的影响。本文针对山区修建高路堤时,研究周围房屋建筑的流场变化,建筑物周围的风环境是人们关注的一个重要指标。本文用Fluent对山区典型区域进行流场分析,研究了不同高路堤及其涵洞对流域内空气流速、大气压强以及湍流度的变化情况造成的影响。探讨了路堤高度、与路堤距离以及涵洞宽度等因素与空气流速与大气压强与湍流度改变量之间的关系。主要得出以下结论:路堤越高,房屋前方空气流速、压强越小,湍流度先增大后减小。与路堤不同的距离改变时,对房屋前方的空气流速以及压强影响轻微;在距离为22m和37m时,湍流度变化较大,其他距离影响较小。涵洞宽度改变时,对房屋前方的空气流速影响很大,宽度越大,空气流速越大;涵洞宽度增大时,压强先增大后减小;湍流度随着涵洞宽度的增大呈现波动性分布。

The air flow field in a typical residential ground in mountainous areas,i.e.houses surrounded by hills on three sides and facing high embankment with culvert,was mathematically modeled,theoretically analyzed and numerically simulated with UG and Fluent software for living environment optimization.The influence of the height/distance of embankment and culvert width on the distributions of air velocity,pressure and turbulence was investigated.The results show that the position and geometry of embankment/culvert have a major impact.For example,as embankment height increases,the velocity and pressure in front of houses decrease,and turbulence intensity changes in an increase-decrease mode;weakly affecting the velocity/pressure,the house/embankment distances at 22 m and 37 m account for the rapid changes of turbulence intensity;and as the culvert-width increases,the air velocity increases and the pressure varies in an increase-decrease manner in front of houses,accompanied by a fluctuating turbulence distribution.