Abstract: The formation and development of the urban climate are closely related to urban construction. High-density urban construction has weakened the flowing wind field in the city, forming a typical urban static wind characteristic. Existing studies have proven that natural ventilation is conducive to improving the quality of human habitation, achieving climate-adaptability planning and design, and low-carbon energy-saving goals. However, studies on the correlation between wind environment and urban morphology suffer from engineering and superficiality in assessing technical routes, insufficient attention to local climates, and improper use of urban wind environment boundaries. The Houhai Central District in Shenzhen is selected as the research object, and the wind environment assessment is taken as the mid-term part of urban planning and design. The double-cycle assessment system based on "urban form, ventilation, and energy conservation" is constructed under the technical route of wind environment assessment of "double cycle" + "multi-scale" nesting, and the local climate boundary condition of "ventilation and energy conservation" in typical time is strengthened. As an urban business district with obvious daytime work attributes, the Houhai Central District is studied in a multi-scale nested study using building morphology data, the meteorological data of the European Centre for Medium-Range Weather Forecasts (ECMWF), and the Meteorological Bureau of Shenzhen Municipality to drive the WRF model for the refined wind-field simulation to obtain the prevailing wind conditions of the Houhai Central District and the climate sensitivity differences of the urban land. The computational fluid dynamics (CFD) model of the Houhai Central District is established, and the high-precision numerical simulation results of the WRF model for the Houhai Central District are extracted as the initial wind-field conditions of the CFD model, and the data transfer between the WRF model and the CFD method is realized to complete the nested operations. The natural months suitable for ventilation in Shenzhen are screened based on the local climate-comfort factor, and the study on energy conservation and emission reduction of urban ventilation potential is conducted from the perspectives of ventilation and energy consumption to quantify the ventilation in the study area in seven different months. The impact of urban natural ventilation on energy conservation under the characterization of building energy consumption per square meter is investigated by studying the comfort months of the Houhai Central District. The wind environment problems in the urban form of the Houhai Central District are visualized from the wind speed, wind-speed ratio, and vortex static wind area with numerical and visual features. The results of the study show that land attribute is an important element affecting the urban wind environment. Water land is the most conducive to improving the urban wind environment, and an appropriate increase in blue and green infrastructure, especially in water areas, can improve the urban wind environment. This is particularly evident in the Houhai Central District. In the Houhai District of Shenzhen, the difference between daytime working conditions and all-day prevailing wind conditions is large. In addition to the meteorological conditions in the all-day prevailing wind direction, the urban wind environment assessment should explore the urban wind environment conditions during the daytime (8:00-20:00) from the performance perspective and reflect the actual usage effectiveness of the wind environment according to the function of the analyzed land in terms of nature. In Shenzhen, the potential for ventilation and energy conservation mainly concentrates in January, February, March, April, October, November, and December. In April, the city has the largest ventilation and the largest ventilation and energy conservation potential, reaching 52.73%. However, the study also has some shortcomings, especially in the southern region, where temperature and humidity need to be considered when analyzing the wind environment. The uneven geographical distribution of meteorological observation stations and the limited duration of station construction also affect the accuracy and authenticity of this study.

Key words: urban morphology, ventilation and energy conservation, wind environment assessment, multi-scale

摘要： 完善风环境评估方法和技术路线的多元性和科学性，为实现城市低碳节能目标、促进气候适应性规划设计提供基础补充。以深圳后海中心区为实证对象，在“双循环”+“多尺度”嵌套的风环境评估技术路线下，构建基于“城市形态及通风节能”的双循环评估体系。研究得出用地属性对局地气候的敏感性差异，水域用地是最低影响的下垫面形式；日间工况与全天盛行风况存在显著区别，典型时段的风速风向表现凸出；显示4月是通风节能潜力最大的月份，可以降低能耗52.73%。多尺度的风环境评估方法可以突破原有单一侧边界条件的限制，从“城市形态及通风节能”两个角度，融合局地气候风环境边界条件，有利于完善规划设计阶段方案评估过程，提高设计方案效益，推动规划设计发展。

关键词: 城市形态, 通风节能, 风环境评估, 多尺度