| Since the beginning of the 21 st century,urbanization has significantly changed the situation of urban underlying surface in China,and the contradiction between urban ecological problems and urban land use has become increasingly prominent,and the comfort of people’s living climate environment has become a hot topic.However,at present,human beings have not yet controlled the macro climate environment,so the improvability and adjustability of local microclimate have become the breakthrough point of urban climate environment research.As the main natural productivity in urban structure,green space’s own functions of shading and cooling,transpiration and cooling,and optimizing wind environment are the most cost-effective strategies to alleviate the malignant microclimate problems.Based on the context,relying on the "urban acupuncture theory",this paper takes the green space design as an important "acupuncture point",explores the possible mechanism of green space to improve the microclimate environment of urban residential areas,and provides some reference for the design of livable home environment in the future.In this paper,taking the green space planning of a residential area in Xuzhou as an example,by analyzing the three-dimensional scale of residential buildings and the design characteristics of residential green space,the universal residential buildings and green space models are selected.The meteorological data of the research area collected by the scientific research level full-automatic hobo meteorological station is used for the initial input value of the digital analog model and for the verification of the model accuracy.The three-dimensional Microclimate Simulation Software envi-met was used to establish a model to simulate and analyze the impact of different green space configuration and different green space amount on the microclimate environment.And through the quantitative and qualitative methods to compare and evaluate the influence of each scheme on the microclimate variables,including the temperature,humidity and the wind environment,the best green space design scheme would be obtained.On this basis,according to the design method of "urban acupuncture",small-scale intervention,I simulated and analyzed the improvement effect of the best green space design and renovation scheme on the surrounding environment.The main work and conclusions are as follows.(1)Under the same rate of green space,seven models were established for different green space configurations,mainly comparing and analyzing the differences of microclimate variables among grassland,shrub,arbor,shrub,shrub and arbor.The order of cooling and humidifying effect of these models is: grassland shrub arbor > shrub arbor > grassland arbor > arbor > grassland shrub > shrub > grassland;the order of reducing wind speed is: shrub arbor > arbor > shrub arbor > grassland arbor > grassland shrub > shrub > grassland.(2)With the same green space configuration mode,the difference of microclimate variable values of different schemes was compared with the increase of green space rate.When the critical value of green space is between 35%-40%,the effect of cooling and humidification tends to be gentle.When the adjacent value is between 25%-30%,the wind speed tends to be gentle.In conclusion,the local green space rate should not be less than 25%,which should be set at 30%-35%.And when the green space rate is less than 40%,the influence of green space internal structure is very important.(3)The design method of "urban acupuncture" is used to set up simulation experiments at the key points of the area center,and then the best green space design scheme is obtained.On this basis,it explores the minimum intervention scheme which can achieve the maximum effect of landscape benefit improvement with green space design as the variable.The results show that the green space model constructed in this paper has a positive impact on the temperature,humidity,wind speed,Radiation temperature and Surface temperature of the surrounding and central areas,and can improve the surrounding microclimate environment. |
