This study analyzed the weather environment of the smart city to identify the temperature reduction effects of the heat reducing facilities. The methodology is divided into indoor and outdoor analyses. Indoor analyses were conducted for the evidence-based design of the facility. The size of nozzle is adjusted to derive the most efficient size for outdoor use. Three types of nozzles were used, 0.15 mm, 0.2 mm and 0.3 mm. The most efficient nozzle was selected as 0.15 mm. The outdoor test was measured for two days from August 3 to August 4, 2020, and the weather data were collected for the control and target sites on the first day. On the second day, the measurements were taken assuming that the temperature and humidity of two sites would be similar. Compared to the control group, the outdoor test site had a temperature reduction effect up to 7.4℃. When operating the heat-reducing facility, the rate of change in sensible temperature is lower than control site. This study concluded that mist facilities have a pre-cooling effect, which means reducing the temperature to a certain level. The results from this study data could be provided when establishing an adaptation policy for a heatwave.

According to a NASA Goddard Institute for Space Studies report, temperatures have risen by approximately 1 °C so far, based on temperatures recorded in 1880. The 2003 heatwave in Europe affected approximately 35,000 people across Europe. In this study, a cooling fog, which is used in smart cities, was designed to efficiently reduce the temperature during a heatwave and its pilot test results were interpreted. A model experiment of the cooling fog was conducted using a chamber, in which nano mist spray instruments and spray nozzles were installed. The designed cooling fog chamber model showed a temperature reduction of up to 13.8 °C for artificial pavement and up to 8.0 °C for green surfaces. However, this model was limited by constant wind speed in the experiment. Moreover, if the cooling fog is used when the wind speed is more than 3m/s in the active green zone, the temperature reduction felt by humans is expected to be even greater. As a second study, the effect of cooling fog on temperature reduction was analyzed by installing a pilot test inside the Land Housing Institute (LHI). The data gathered in this research can be useful for the study of heat reduction techniques in urban areas.