Research On Dynamic Changing Regularity And Prediction Method Of Outdoor Thermal Comfort In Harbin

The residents’ thermal comfort should be considered in the period of city construction and designing,so the study on outdoor thermal comfort is becoming the focus of researchers.But most of the studies were carried out in tropical or hot summer and cold winter region,and rare in severe cold region.In order to study the dynamic change of outdoor thermal comfort in severe cold region and establish predicting model.A tracking questionnaire survey was carried out in Harbin,which is severe cold city.And some following analysis work was conducted.31 graduate students were selected to take part in the survey for a period of one year,and one day about every other week was chosen to carry out questionnaire investigation.And in the meantime,air temperature,relative humidity,wind and solar radiation were measured comtinuely.Based on the questionnaire and meteorological data,the following results were obtained.Based on the analysis of the changes of thermal sensation and thermal comfort,it was found that the two had obvious seasonal characteristics.The study of the influence factors of thermal sensation showed that the thermal sensation in spring,autumn and winter was significantly correlated with air temperature and radiation,and significant correlation between thermal sensation and air temperature,relative humidity and radiation was found in summer.Second,people’s tolerance to the environment is also influenced by sex and length of residence time in severe cold areas.The changes in year-round thermal comfort voting were analyzed.It was found that the outdoor comfort was better in spring,summer and fall,and more than 50% uncomfortable votes showed that the outdoor environment in winter was bad.After that,the relationship between thermal sensation and thermal comfort has found to be different between seasons.Then,predicting models of outdoor thermal comfort in severe cold area were established.Based on the meteorological and physiological parameters,PET and SET* was calculated by Rayman.Linear relationship between thermal sensation and PET or SET* were obtained respectively.By analyzing the relationship between air temperature and clothing thermal resistance in different seasons,behavioral adajustement was found.And it was found that in severe cold regions,thermal sensation is less sensitive to the changes of PET and SET* than in other regions.In winter,the neutral PET in severe cold area was lower than that of other seasons,which indicates the exists of psychological adaptation.By comparison of the slope of thermal sensation and SET* equation in severe cold area and Hongkong,it is found that the greater the temperature difference between indoor and outdoor environment,the more sensitive people are to outdoor environment.Finally,by multiple linear regression,the thermal sensation predicting model of different seasons and the whole year was obtained.According to the nonlinear fitting,models for predicting thermal comfort in different seasons and full year by thermal sensation were obtained.These models included people’s adaptability to the environment,and shows that people have different requirements for comfort in different seasons.