Effects of thermal and acoustic environments on human comfort in urban and suburban campuses in the cold region of China.

In this study, we investigated the effects of thermal-acoustic environments on human comfort in a cold region by focusing on Xi'an in China as a representative city. Four typical open spaces were identified within two universities, with one located in an urban area and the other in a suburban area. Surveys were conducted using questionnaires and environmental parameters were measured to assess thermal-acoustic perception. The physiological equivalent temperature (PET) and noise sound pressure levels were employed to measure the thermal-acoustic environments in the four open spaces. The results showed that the neutral PET was 19.1 °C in Xi'an from March to May, and the neutral temperature range was 14.9-23.4 °C. The preferred temperature was 20.0 °C. Acoustic sensation votes were lower in suburban areas than urban areas. Respondents in urban areas exhibited significantly higher sensitivity to the thermal and acoustic environments compared with those in suburban areas. Sensitivity to the thermal environment decreased as the environmental noise levels decreased. The temperature perceived as most suitable increased as the sensitivity to the thermal environment decreased. Acoustic comfort evaluations were generally higher in colder and warmer environments. Warmer environments heightened the sensitivity to the acoustic environment and this effect gradually decreased as the sound pressure levels increased. Thus, based on empirical analyses, we compared the effects of outdoor thermal-acoustic parameters on comfort to provide experimental data support for further outdoor thermal comfort research.