The Effects of Windbreak Forests on the Summer Thermal Environment in a Residence

As urbanization progresses, the outdoor thermal environment is deteriorating due to the decrease of vegetation and increase of constructed surfaces. Environmental problems such as the heat island phenomenon occur not only in large cities but also in mid-sized and small cites. Increasing tree or vegetation plantings is one of the most effective strategies to mitigate environmental problems and create a comfortable living environment. In this study, the microclimatic effect of a windbreak forest surrounding a residence was analyzed based on field measurements and numerical simulation results. Spherical thermographs of surface temperature distribution observed in an actual residence were used to identify the thermal effect of the windbreak forest and surface materials. A coupled numerical simulation method of computational fluid dynamics (CFD) and outdoor thermal simulation was used to evaluate the microclimate and thermal comfort in outdoor living spaces. The proposed simulation method was validated by comparing the simulated results with the measurement data. In addition, the residence was modeled using the coupled simulation program to quantify the microclimate and outdoor thermal comfort. Simulation results show that this simulation method is capable of predicting the solar shading effect and wind speed reduction due to trees as well as thermal improvement from decreased ambient air temperature and surface temperature.