Study On Outdoor Thermal Comfort Of Existing Residential Areas In Chongqing During Summer

During the rapid development of urbanization,the population of urban communities continues to increase.The outdoor space of residential areas has become an important place for human activities.A good residential environment can provide residents with comfortable and healthy leisure spaces.The evaluation of outdoor thermal comfort has important guiding significance for creating a good outdoor environment quality.However,the current research focuses more on outdoor areas such as business districts and campuses.There are few studies on outdoor thermal comfort in residential areas,and there is no accurate and applicable evaluation model for outdoor thermal comfort in residential areas in Chongqing.Therefore,this study takes the existing residential area of Chongqing as the research object to carry out the research on outdoor thermal comfort of residential area.First,through research on the current status of Chongqing’s existing settlements,the residential areas of Yubei A and Shapingba B in Chongqing with high occupancy rate and abundant underlay types are selected as research sites.According to the outdoor thermal comfort research standards,I formulate questionnaires and experimental plans,and conduct experimental tests in residential areas A and B from July to August 2018 and July to August 2019,respectively.The experiment is used to obtain the outdoor ambient air temperature,relative humidity,wind speed,black ball temperature,and solar radiation in the residential area.During the experiment,a questionnaire survey is conducted simultaneously.The survey data of settlement A is used for analysis and evaluation model establishment,and the survey data of settlement B is used for model verification.Then,a comprehensive analysis of the survey results was carried out,comparing the frequency distribution of the respondents’ heat,humidity,wind,radiation sensory voting and preference.This article explores the quantitative relationship between outdoor thermal comfort satisfaction,unsatisfactory factors,and the percentage of MTSV and unacceptable rate.The article summarizes the time distribution of outdoor thermal comfort levels in residential areas,and analyzes the impact of respondents’ outdoor stay time on thermal sensation.At the same time,the article studies the relationship between outdoor thermal comfort and thermal sensation,and analyzes the adaptability of the interviewees in the residential space.Next,this paper studies the applicability of PMV,PET,SET~* and UTCI in the outdoor environment of Chongqing residential areas;separately discusses the quantitative relationship between Ta,RH,V,Tmrt,SR and MTSV.On this basis,the article uses SPSS to perform regression analysis on the survey data,and adopts a gradual elimination method to establish independent variables and establish a comprehensive evaluation model of outdoor thermal comfort in Chongqing’s residential areas..Finally,based on the preliminary field measurement and survey data,the ENVI-met simulation software platform is selected.Based on the above model,for areas with high residential activity rate but poor thermal environment,the optimal transformation study was conducted by changing the tree canopy density and road surface reflectance.Through the above research,the summer outdoor thermal comfort status of residents in Chongqing settlements is revealed,and the evaluation model of outdoor thermal comfort in Chongqing settlements is established.The improvement effect of arbor canopy and road surface reflectance on the outdoor thermal environment comfort in residential areas was explored,and an improvement strategy to improve arbor canopy and road surface reflectance was proposed.It is expected to provide theoretical support for the design,planning and renovation of the outdoor environment of Chongqing residential areas.