Comfort-based design of summer green space optimization in arid oasis-type cities

Arid, oasis-type cities significantly limit the quality and duration of outdoor activities for residents due to their hot, dry summer climate. This study aims to enhance environmental comfort in dry, hot regions, focusing on the outdoor environment of a densely populated university in Xinjiang. Through on-site research and field measurements, the thermal baseline and key factors influencing comfort across different times and locations were analyzed. Numerical simulations were employed to explore the mechanisms by which changes in vegetation parameters affect comfort, leading to the proposal of an optimization strategy. The results indicate that a combination of empirical measurements and survey data reveals variations in thermal baselines and comfort-affecting factors over time and space. The neutral temperature ranged from 26.10 °C to 26.96 °C. Key factors affecting summer comfort included G (0.91∗∗), T_a (0.74∗∗), and RH (−0.57∗∗). The impact of vegetation coverage on PET was found to depend on the type of vegetation assembly. In comparison to the baseline case at 18:00, the optimized plaza design resulted in a decrease in T_a, etc by 2.86 °C, an increase in RH by 3.42%, a reduction in V_a by 0.01 m/s, and a reduction in PET by 24.62 °C. These enhancements also improved comfort levels on nearby roads. The findings provide valuable insights for assessing human comfort and designing green spaces in arid regions.