Urban Ventilation Simulation And Planning Strategy Of Medium-Micro Scale In Urban Waterfront Based On Porous Media Model

With the rapid development of economy and society,urbanization has not only brought about fruitful results of urban construction,but also brought about a negative impact.The large amount of man-made heat emission in the city has caused severe impacts on the natural environment and ecological environment.The urban heat island phenomenon is one of the most significant effects of human activities on the climate system.The higher urban environmental temperature seriously affects the lives of citizens and the overall environmental quality of the city.Urban ventilation can not only alleviate the heat island effect caused by urban expansion,but also release various pollutants in the city and play a positive role in protecting the urban ecological environment.In cities,water bodies can also effectively alleviate the urban heat island effect and become the its "cold source".The breeze generated by the difference in the thermal properties of the underlying surface of the land and water can effectively promote the air circulation in the city.The construction of river-type ventilation corridors is an important part of urban ventilation corridors.The research and discussion of river-type ventilation corridors has become one of the important contents of urban wind environment research.This study first summarizes the main theoretical methods,technical means and related research progress of urban ventilation and water body climate effects,and proposes an improved quantitative wind environment simulation method for urban rivers to simulate the urban wind environment at the partition level.At the same time,the accuracy of the model is verified by comparing the simulation results with the sub-environment simulation results through the proposed actual measurement scheme Secondly,this study decomposes the wind environment planning tomography by analyzing the case of wind environment planning and combining the national spatial planning system,and puts forward quantitative research techniques at all levels.Aiming at three levels of meso-micro scale,a quantitative simulation framework for wind environment planning is proposed.Thirdly,the study takes the typical area of Hangzhou Jinghang Canal(Gongshu Section)as a case,simplifies its urban built environment into a porous medium model,and uses the improved wind environment quantitative simulation method to numerically simulate the wind environment in the area and carry out the results.After analyzing and discussing the ventilation performance of different types of urban spaces,optimization strategies are proposed.Based on the simulation results,a detailed simulation of the streets with poor ventilation potential is conducted to analyze the problems in the wind environment and corresponding optimization strategies are proposed.Finally,from the perspective of land and space planning transformation,a medium-micro scale wind environment planning and design framework is proposed to determine the working methods of wind environment assessment,wind environment zoning,control indicators and optimization strategies,and corresponding planning for urban waterfront is proposed with strategy.