城市大气环境的数值模拟

Numerical Simulation of City Atmospheric Environment

空气质量是城市可持续发展的保证,是改善人居环境的重要条件之一。大气环境是多尺度的流体运动,本文介绍了城市尺度和居民小区尺度大气环境的现代数值预测方法——大涡数值模拟方法,着重说明该尺度下复杂环境流动的特点和数值模拟需要注意的问题,例如下垫面的处理方法、边界条件的合理提法等;以典型城市和模型小区为例,说明数值预测方法的应用,展示不同下垫面对城市大气环境的影响、风速与小区空气质量的关系等。

Air quality is one of essential conditions for essential development for modern cities and is an important factor in the resident environment. The atmospheric environment is a multi-scale fluid flow. This paper discusses modern numerical methods for predicting atmospheric environment in a city and resident area. Particular emphases are put on the peculiar feature of this complex environmental multi-scale flow and the problems that need to be tackled, for instance, the treatment of the complicated canopy catalog and the boundary conditions. The application of the numerical method is illustrated by two examples, a typical city and a model resident area. The influence of canopy catalog on the city atmospheric environment is demonstrated and the relationship between wind speed and air quality in the resident area is obtained.