Effects Of Typical Building Layouts On Microclimate Of Urban Residential District In Hot And Humid Region Of China

The building layout of the residential district is an important component of the urban spatial form,which has an important impact on the local microclimate environment.In recent years,the accelerating urbanization process has led to the intensification of urban heat islands,and the problem of the deterioration of the microclimate environment of urban residential communities has received increasing attention.Reasonable planning of the building layout of the residential district,not only can effectively improve local microclimate conditions(mainly the wind environment and thermal environment conditions of the residential district),and alleviate the impact of adverse climate phenomena such as the urban heat island effect,but also can improve the outdoor comfort of the residential district,reducing the energy consumption of residential buildings,and avoiding extreme weather(such as heatwaves,etc.)have adverse effects on the health of urban residents.Therefore,it is of great significance to study the effects of the residential building layout on the local microclimate.In this article,the microclimate of residential districts of the typical city(Guangzhou City)in hot and humid regions is taken as the main research object.By reading relevant domestic and foreign literature,four typical building layout forms(row layout,staggered layout,indented layout,and enclosed layout)are summarized and extracted.Combined with the basic principles of urban climatology,heat transfer,thermodynamics and computational fluid dynamics(CFD),by using the typical meteorological day and extreme meteorological day in summer of Guangzhou as meteorological background conditions,the three-dimensional microclimate simulation software ENVI-met was applied to performs a numerical simulation of the microclimate of the residential district.Through the comparative analysis of the four parameters of air temperature,relative humidity,wind speed,and standard effective temperature SET at the pedestrian height,the laws of the influence of the building layout of urban residential districts on the local microclimate are discussed.The main conclusions of this article are:(1)Under typical meteorological day conditions in summer,the order of outdoor temperature environment is enclosed layout > indented layout > staggered layout > row layout;while in summer extreme weather day conditions,the order of outdoor temperature environment is enclosed layout > staggered layout > row layout > indented layout.(2)The trend of the average relative humidity changes from time to time in the four building layout forms is consistent.During the simulation period of the typical meteorological day in summer,the order of the outdoor relative humidity of each building layout is enclosed layout > indented layout > staggered layout> row layout;during the simulation period of the extreme meteorological day in summer,the result is enclosed layout > staggered layout > row layout > indented layout.(3)Whether it is the typical meteorological day or the extreme meteorological day in summer,the average wind speed difference between the four building layout forms is not large.Combining the simulation results of the typical meteorological day and the extreme meteorological day in summer,the order of the outdoor wind speed environment of the four building layout forms is staggered layout > row layout > indented layout > enclosed layout.(4)At different moments,the relationship between the average SET value of each building layout is different.Combined with the average daily SET value and SET value distribution,by analyzed the simulation results of the typical meteorological day in summer,the outdoor thermal comfort of the enclosed layout is the best,followed by the indented layout and the row layout,and the thermal comfort of the staggered layout is poor;while by analyzed the simulation results of the extreme meteorological day in summer,the outdoor thermal comfort of the enclosed layout is the best,followed by the row layout and staggered layout,and the thermal comfort of the staggered layout is poor.