Research On The Optimization Strategy Of Thermal Comfort During The Transition Seasons For Small Sclae Public Spaces In Winter Cities

With the advancement of healthy cities,the construction of urban public space cannot be limited to the consideration of urban landscapes.It is also important to pay attention to urban health issues,while climate adaptive design has gradually become an important means to deal with urban health problems.The climatic environment of the winter cities is relatively harsh,and the outdoor activities are largely affected by the climatic environment.Improving the outdoor thermal comfort is of great significance for improving the vitality of the city.The urban small-scale public space is the most accessible outdoor space for urban residents,and its actual use reflects the actual needs of residents' lives.Therefore,this paper took the small-scale public space of winter cities as the research object,and explored the relationship between the crowd behaviors and the space thermal comfort,in order to provide theoretical support for the planning and design of small-scale public space in the winter cities.The study was carried out in the transition season.In order to obtain more targeted conclusions,the transition season is divided into the comfort phase and the edge phase to compare the thermal comfort.Three types of small scale public spaces with different theme functions in Harbin were selected as the research objects,where through field observation,instrument measurement and questionnaire survey,the characteristics of the activities,microclimate environment,as well as people's perception of the thermal environment were explored during autumn.Based on the analysis of crowd behavior aggregation model and public space thermal comfort,the relationship between space-time distribution and thermal comfort of population activities was preliminarily established.Through multivariate regression analysis of microclimate parameters and thermal comfort evaluation,the degree of influence of microclimate factors on the thermal comfort of square space,rest space and instrument activity space was explored.The influence of space environment elements such as surface type,plant configuration,and activity facilities on the thermal comfort of different spaces.Then,through the regression analysis of physiological equivalent temperature,the influence of spatial environmental factors,such as spatial enclosure degree,shading type,underlying surface type,plant configuration and activity facilities,on the thermal comfort of different spaces was quantitatively analyzed.The result shows that compared with the comfort stage,the differences in thermal comfort perception of the space at the marginal stage are significantly increased.The low degree of enclosure and high-reflectivity paving materials are beneficial to improve the thermal perception of the square.Compoundrest facilities,low canopy closure and single-sided enclosure on the north side are conducive to the thermal comfort of the rest space.While the thermal comfort of the equipment fitness space is mainly affected by the mode of activity,and the microclimate environment only plays a supporting role.Based on this,the optimization strategy of small-scale public space is proposed to meet the thermal comfort needs of urban residents in cold regions,so as to contribute to the improvement of vitality of small-scale public space in cold regions.