Investigation on outdoor environment based on UTCI for the campus in high humidity area: A case study in Nanchang, China

The outdoor environment of campuses in high-humidity areas greatly affects personnel comfort and health. An optimized analysis model based on the Chen–Kim k – ɛ turbulence model, integrated with the IMMERSOL radiation model and Foliage vegetation model, to characterize the outdoor thermal-humidity environment of a Nanchang campus, with its reliability verified by experiments. Firstly, the Universal Thermal Climate Index (UTCI) and related environmental parameters are simulated and analyzed during key periods of a typical summer day. Then, multiple linear regression is used to explore the relationship between UTCI and its influencing factors. The results show that UTCI, ambient temperature and mean radiation temperature in building pedestrian zones are significantly higher than in other areas, peaking at 40.6 °C, 41.3 °C and 43.73 °C respectively at 14:00. In contrast, relative humidity in these zones is lower, reaching the minimum of 44.9% at 11:00. Furthermore, the proposed UTCI regression model for the Nanchang campus only requires outdoor temperature and wind speed for estimation, greatly simplifying calculations. This research provides a theoretical basis for evaluating outdoor thermal comfort in actual campus settings.