Thermal response and thermal comfort evaluation of the split air conditioned residential buildings

Abstract

In China, split air conditioned (SAC) buildings operate in manual changeover mixed-mode (MM) that integrates air conditioned (AC) mode and natural ventilation (NV) mode in summer. In order to understand the thermal response of such buildings and determine the thermal comfort evaluation method, 522 data were collected from residential buildings in Jiaozuo. In summer, occupants in AC mode had a cooler thermal history than in NV mode because the mean operative temperature in AC mode was lower than in NV mode. And the occupants in AC mode felt cooler, drier, windier, more comfortable and had greater acceptability than occupants in NV mode, but the upper limit of 80% acceptable temperature was close, about 30 °C. Short-term indoor thermal history mainly affects thermal sensation and thermal preference, while perceived control mainly influences thermal comfort and thermal acceptability. The different operating modes in summer have no significant influence on the thermal adaptive ability of occupants, so the thermal comfort of SAC buildings could be evaluated as a whole. When the outdoor temperature is below 30 °C, occupants can take advantage of physiological, psychological and behavioral adjustments to improve their thermal comfort, so adopting the adaptive model for evaluation is recommended. However, when the outdoor temperature exceeds 30 °C, the above adaptative opportunities are limited, and the upper limit of acceptable temperature for occupants is 30 °C. This study promotes the understanding of the impacts of different operating modes on thermal response, and provides support for the thermal comfort evaluation of SAC buildings.