Investigation on the Influence of Insolation on Winter Thermal Comfort of Outdoor Activity Space on Campus in a Cold Region of China

With the development of various outdoor activities on campus, students are spending increasingly more time in the outdoor space, so the outdoor environment has a more important impact on students’ physical and mental health. Targeting a typical outdoor activity space of a university in Xi’an city, which is located in the cold region of China, this paper investigated its winter thermal comfort performance through on-site measurement, a questionnaire survey, and statistical analysis. The collected data were analyzed by SPSS software, and the functional relationship between TCV (thermal comfort voting value) and outdoor environmental parameters was established. Along with the questionnaire survey, solar radiation, wind speed, and air temperature of two specific positions (P1 and P2) was measured and recorded in real time. The results showed that, under similar clothing thermal resistance, in the area without sunlight (P1), the measured air temperatures range between 3.2 °C and 13.1 °C and wind speed range between 0 and 1.8 m/s. The survey respondents wanted to improve thermal comfort by increasing the temperature. In contrast, in the area with sunlight (P2), the temperature range between 3.6 °C and 16.2 °C and wind speed range between 0 and 1.9 m/s, the survey respondents wanted to improve the thermal comfort by decreasing the outdoor temperature. Such results imply that insolation significantly affects the winter thermal comfort sensation of outdoor activity space on campus.