Analysis of Regulation Characteristics in Acceptable Thermal Comfort Zone under Cooling Conditions

Residents mainly set the temperature at the range of 25°C to 27°C under cooling conditions. However, they may feel uncomfortable after staying a period in a steady-temperature environment. To make themselves more comfortable, residents will change their postures and even regulate the temperature. To analyze the regulation characteristics, this study combined thermal environment testing, questionnaire survey, video collection, and data mining methods to collect the thermal environment and comfort background, posture, and temperature regulation characteristics. The results showed that Mean Thermal Sensation Vote gradually deviated from neutrality and tended to be cooler even though the thermal environment and thermal comfort were both within the acceptable zone. 12 typical posture regulations were captured and divided into 3 categories: head (face) postures, trunk postures, and limb postures. Head (face) postures were the concentrated expression of adaptive postures (80%). Although the total posture frequency remained unchanged, the head (face) postures gradually increased, which reflected the increase in discomfort. The temperature regulations accounted for nearly 25%. Most people (90%) regulated the temperature at 1 °C with the frequencies of once or twice, and they preferred to set the temperature up than down. In the first 3 hours, there would be a regulation peak every 20 or 30 minutes, while the regulation decrease after 3 hours.