基于遥感和CFD模拟的城市居住区布局形态的热环境影响机制与调控机理

Urban land sprawls rapidly while urban land planning is lack of its environmental effects, and the thermal environmental problem in urban development process is still very evident and crucial for sustainable city. By the combination of new technologies with traditional methods, we study the effect of urban land change on thermal environments in a micro scale. The study has been the hot point in related research fields. Around the response mechanism of thermal spatial pattern on urban residential spatial pattern and its regulation methods, there are four key research points: (1) Based on the multi-source data such as LiDAR images, we extract residential land spatial units and make the three-dimensional reconstructing for residential spaces, and by the combination of urban morphology with landscape metrics present the spatial pattern metrics and their spatial characteristics. (2) Loading residential ground physical model and boundary parameters, the CFD model is verified and evaluated by the use of field monitoring, and the vertical and horizontal pattern of the residential physical environments temperature. (3) Taking other boundary parameters as the constants, the parameters of spatial pattern is regarded as independent variables and inputted individually into the CFD model. Then by the analysis of the relationship between independent and dependent variables the effect mechanism of urban residential spatial pattern on thermal pattern is revealed. (4)By making different spatial pattern scenarios and the relationship between spatial patterns -temperature pattern parameters based on CFD model, we reveal the effect difference of residential spatial pattern on thermal environments and put forward the controlling measures according to the different influence areas. The study aims to understand the effect mechanism of urban land change on urban heat island in spatial micro scale, and helps providing the guidance of other urban functional areas planning, and provides the scientific base of urban residential land planning in sustainable development.

城市用地持续扩展而其利用的热环境考虑仍不足，城市热环境问题难显缓势。融合新技术和传统方法，从微尺度理解城市用地变化的热环境响应机理成为相关研究的热点。围绕城市居住区布局形态的热环境响应与调控，研究重点有四：（1）基于LiDAR等多源数据提取居住空间类型并三维重建，综合城市形态和景观指数分析布局形态分异特征；（2）载入地物模型及边界条件，以实测数据验证评价CFD模型，分析居住区输出温度的垂向和水平格局；（3）维持其他边界参数不变，逐调CFD模型布局形态参数自变量，分析输出温度与自变量互动关系，揭示布局形态对热环境影响方式与程度；（4）设置居住布局形态方案，通过CFD模型及布局形态-温度互动关系，评估各布局形态方案的热环境影响差异，并针对不同影响区提出调控对策。该研究是从微尺度上理解城市用地变化对城市热岛的形成机制，为其他城市功能区类型研究提供思路，也为城市住区规划的热环境评估提供依据。

我国城市化持续快速发展，城市热环境问题难显缓解之势，而城市空间利用与规划的热环境影响考虑仍不足。本项目围绕城市居住区布局形态的热环境响应与调控机理展开研究，已取得以下研究成果：（1）基于LiDAR、多光谱遥感等多源遥感数据探讨居住区三维模型的建立方法。探讨了LiDAR数据滤波、建筑物边缘提取和三维建模算法，并将该算法应用于重建居住区的三维模型；（2）检验、评价与校正了CFD模型。以实测数据验证、评价CFD模型，提出了影响CFD模型的敏感参数；根据研究区特点，对CFD模型敏感参数进行率定，提高了CFD模型模拟的精度，拓展了CFD模型的应用范围；（3）模拟并研究了建筑设计要素对居住区热环境的影响。维持其他边界参数不变，逐步调整模型布局形态参数自变量，分析模拟输出参数与自变量互动关系，探讨了绿地数量、绿地类型、绿地格局；建筑物高度、建筑物密度和建筑物布局对热环境影响方式与程度；（4）针对实际居住区，从绿地、建筑物布局等方面提出了热环境调控对策。该研究是从居住区尺度上理解建筑设计对城市热岛的形成机制，为其他城市功能区类型研究提供思路，也为城市住区规划的热环境评估提供依据。