Analysis of Thermal Environment Modification Effects of Street Trees Depending on Planting Types and Street Directions in Summertime Using ENVI-Met Simulation

The modification effects of street trees on outdoor thermal comfort in summertime according to tree planting types and road direction were analyzed using a computer simulation program, ENVI-met. With trees, the air temperature wind speed decreased, relative humidity increased. In case mean radiant (Tmrt) human sensation, physiological equivalent (PET) universal climate index (UTCI), there was decrease during daytime. greatest change among meteorological factors by happened Tmrt, PET UTCI showed similar patterns with Tmrt·The most effective type low height, wide crown, high leaf area index, narrow interval (LWDN). large difference depending shadow buildings solar altitude azimuth angles, building locations. When shade areas increased, effect decreased. particular, results east west sidewalks deviation over time. applying LWDN, northwest, southwest significant reduction 8.6-12.3°C 4.2-4.5°C at 10:00, northeast, southeast 8.1-11.8°C 4.4-5.0°C 16:00. On other hand, when least (high interval) applied, maximum up 1.8°C 0.9°C eastern sidewalks, 3.0°C western ones. addition, between not reduced buildings. These can be used as basic data make appropriate model for improvement urban summer.