Research On The Outdoor Thermal Environment At Tianjin University Campus In The Summer

As the climate warming up, the heat island effect has become an insurmountableissue in urban development. Meanwhile, the urban thermal environment hasincreasing effects on people’s outdoor activities, especially on students’ college lives.In this paper, take Tianjin University campus for example, the research combinescomputer simulation with environmental parameters test, and the effects of differentenvironmental greening rate on summer outdoor thermal environment are studied. Themain work is as follows:(1) Based on the research review of urban thermal environment, the influence ofenvironmental design factors on outdoor thermal environment is analyzed, and thefeasibility of computer simulating outdoor thermal environment is explored. Thecurrent study of thermal environment is mainly about three aspects, including themicro-climate, heat island effect and thermal comfort. In the environmental greeningdesign, five measures, such as parks and trees, could be taken to improve outdoorthermal environment, and these changes can be predicted through computersimulation.(2) Outdoor thermal environmental parameters are tested, analyzed and evaluatedin Tianjin University campus in summer. Parameter tests include air temperature,relative humidity, wind speed and temperature of the black balls in the pedestrianheight, calculating the thermal comfort index standard effective temperature (SET*).By analyzing test data, the effects of different design factors on environmentalparameters are understood, and campus outdoor thermal comfort can be improved byproper environmental planning and design.(3) Calibration and sensitivity of ENVI-met simulation software are performed.The software simulation principles are followed by necessity of Calibration andsensitivity with a combination of environmental measurement and simulation.Calibration includes vertical grids, nesting grids and boundary conditions, with themeasured environmental parameters to validate the model. Sensitivity analysis is toenable different design factors reflect the thermal environment in the softwaresimulation accurately. (4) Projects with different greening rate are simulated in the calibrated mode to forecast and evaluate the effects of greening rate on outdoor thermal environment. Research results confirmed that increasing the greening rate of the existing environment can improve outdoor thermal environment in summer, but the limitations of green cold is also pointed out, namely that the ambient temperature would infinitely close to a certain value with further increasing greening rate.