Study On The Influence Of Campus Avenue On Microclimate

The development of higher education has put forward higher requirements for running schools.China’s university campuses gradually show a trend of high-density development,and the number of students increases significantly.The tree-lined space on campus is an important part of college campus,carrying most of the informal communication between teachers and students on campus,and also an important space for teachers and students to travel on foot.Therefore,this paper obtains the microclimate information of a university avenue in Guilin by means of investigation and measurement.ENVI-met software was used to carry out numerical simulation of various working conditions,aiming to study the regulation effect of different types of campus avenue,the height to width ratio of the avenue and the diameter of the street canopy on microclimate,and put forward the evaluation model of campus avenue thermal comfort suitable for hot summer and cold winter areas,providing scientific basis for the design and improvement of college avenue.First of all,this paper conducted a field survey on a university avenue in Guilin.Through field measurement and questionnaire survey,the microclimate parameters of the avenue and subjective feelings of pedestrians were collected.The results show that the temperature of the single arch enclosed shady space is lower than that of the two open avenues,while the relative humidity is higher than that of the two open avenues.When the diameter of plant canopy was larger,it had better shading effect on solar radiation,and the temperature of the underlying surface of the canopy was much lower than that of the canopy with poor shading effect.The respondents’ satisfaction with the thermal comfort of the single-arch closed avenue was higher than that of the two-row open avenue.89% of respondents believed that the mall ENVIronment had an impact on campus microclimate,and more than 70% of respondents suggested using tall trees with large canopy diameter to optimize the microclimate of campus mall.Secondly,based on the measured data,with the aid of ENVI-met software to establish the campus avenue and around the 3D model of the space,the thermal ENVIronment simulation analysis under different working conditions,the results show that the two lines open type mall space reduced ratio,ENVIronmental temperature is higher,relative humidity,UTCI value higher,the pedestrian thermal comfort;When the canopy diameter increases,the space temperature of the avenue decreases,the relative humidity increases,the UTCI value decreases,and the thermal comfort of pedestrians increases.When the height-aspect ratio of the single arch closed shade space decreases,the ambient temperature decreases,the relative humidity increases,the UTCI value decreases and the thermal comfort of pedestrians increases.With the increase of canopy diameter,the space temperature of the avenue decreases,the relative humidity increases,the UTCI value decreases,and the thermal comfort of pedestrians increases.Finally,through comprehensive analysis,a prediction model of thermal comfort evaluation based on UTCI index is proposed for campus avenue in hot summer and cold winter areas.The prediction model shows that the wind speed of the mall ENVIronment is not a significant index that affects the thermal comfort model of the mall.By screening the independent variable factors,the optimization model of the thermal comfort evaluation of the mall was obtained,which took the air temperature,relative humidity and solar radiation intensity of the mall as the independent variables of the prediction equation.Based on the simulation,a campus avenue optimization scheme was proposed by changing the height to width ratio and canopy diameter of the avenue.