Research On Urban Morphology Modeling And Numerical Simulation Of Microclimate Based On Local Climate Zons At Macro Scale

The construction of the city has produced a microclimate that is different from the natural climate.The large-scale expansion of the city has brought many adverse effects on the urban climate and seriously affected the quality of life of urban residents.The influence of urban form on microclimate has become a consensus,but for the overall shape of the city,there is still no quantitative analysis related to the microclimate effect.In order to explore the relationship between urban morphology and microclimate at the macro scale,the paper focuses on urban morphological modeling and microclimate numerical simulation methods based on local climate zones(LCZ)theory.The LCZ theory expresses the structure and parameter characteristics of the urban canopy by establishing qualitative and quantitative description indicators of the overall physical characteristics of the underlying surface.The quantitative description method of LCZ theory provides a method basis for constructing the overall urban form implicit model by parameter parameter parameterization on the macro scale.However,the implicit model with many index parameters quantified,due to its abstraction and parameterization,CFD numerical model does not provide very good simulation platform support.The Weather Research and Forecasting Model(WRF)used in meteorological research in the field of meteorology is also a quantitative indicator description of the simulated area using a comprehensive range of surface indicator parameters.Therefore,the LCZ theory and the WRF simulation platform provide a tool basis for the construction of numerical models of urban morphology and microclimate numerical simulation methods.The paper adopts the basic classification framework concept used in urban heat island research to describe the characteristics of urban underlying surface-LCZ theory,and takes the main urban area of Nanjing and its surrounding areas as the research case to construct a numerical model of urban morphology under macro scale.Through quantitative analysis of the LCZ theoretical model,spalial distribution clustering index(IODs)and urban "blue-green" ecosystem analysis,the macro-scale morphological features of the study area are summarized,which provides a data foundation for constructing a typical spatial layout pattern of macro-scale urban forms.Similarly,this paper studies the WRF simulation platform under the discipline of meteorological environment to simulate the urban microclimate environment.By analyzing the principle of quantitative parameters behind the LCZ theoretical model and the mesoscale WRF numerical model,a method for setting the macroscopic urban shape numerical model into the WRF simulation platform is established.The numerical model data provided by the WRF official website and the LCZ theoretical model are simultaneously simulated,and the inadequacies of the original numerical model of WRF are analyzed,and the advantages and feasibility of analyzing the LCZ theoretical model are discussed.The paper further uses the LCZ theoretical model as the data foundation,selects the building height,the city's dominant wind direction,the orientation,the homogeneous distribution and other factors closely related to the urban form,and constructs a highly guided,wind-guided,orientation-oriented,and homogenized.Guided four categories of macro-scale urban typical form space layout form.The above numerical models of each type were placed in the WRF numerical simulation platform for numerical simulation of urban microclimate.For the comparative analysis of each category of microclimate simulation,the preliminary analysis of the relationship between the four types of macro-scale urban typical spatial layout patterns and urban microclimate.