Field study on thermal comfort of naturally ventilated residences in southwest China

Abstract

Kunming, a city in southwest China, has a climate that is different from most of the other places in the world because of its unique geographical characteristics. Due to its temperate climate, most of the residential buildings in this region are naturally ventilated. Accordingly, a winter thermal comfort study was conducted in Kunming to reveal the thermal response of residents. Indoor and outdoor environmental parameters were measured, and participants were investigated about their clothing, thermal sensations, thermal preferences, and thermal acceptance using online questionnaires. Data from 162 valid questionnaires were collected in the survey. Although the climate is referred to as “mild”, the survey showed that the indoor temperature during winter was lower than the typical comfort range. Nevertheless, the participants responded that most of them felt neutral and comfortable. The neutral temperature of participants living in Kunming was determined to be 16.96 °C. The acceptable thermal sensation vote (TSV) range of the residents is −0.72 to 1.52. The acceptable indoor air temperature range is 15.03 °C to 19.55 °C, and the optimum indoor air temperature is 17.2 °C. According to this study, the existing thermal comfort evaluation models can hardly predict residents’ thermal responses in Kunming well.

Keywords

thermal comfort / field study / thermal adaptation / mild climate / natural ventilation

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