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Facial skin temperature has been applied to evaluate thermal comfort in a few studies, but the related theoretical basis is not sufficient. We conducted a climate‐controlled experiment in winter. The air temperatures were 12, 15, 18, 21, and 24°C, and the relative humidity was set to 60%. During exposure (140 min), the subjects were in a sedentary state, and their thermal sensation, comfort, and acceptability of perceived thermal environments were documented many times. iButton instruments were used to continuously and automatically record skin temperatures on the forehead, nose, right ear, right cheek, left cheek, left ear, and chin. The measurement accuracy of the corrected skin temperature was within 0.1°C after calibrating each i‐Button. The experimental results showed that the skin temperatures at different measurement points varied significantly. The forehead skin temperature was the highest, whereas the nose, being the facial part, exhibited the lowest skin temperature (except 24°C). The uneven degree of the skin temperature distribution increased as air temperature decreased. Correlation analysis confirmed that the facial skin temperature can be used to evaluate thermal sensation. Nose skin temperature and the average skin temperature of the forehead, nose, and chin are the most suitable indicators of thermal sensation. The correlation between facial skin temperature and the thermal sensation was significantly higher after 15 min of exposure time than that during 0–15 min. This study provides a theoretical basis for using facial skin temperature to dynamically monitor thermal sensations. [ABSTRACT FROM AUTHOR]

A method to develop an adaptive thermal comfort model based on the running mean outdoor temperature for Chinese people was proposed. The determination of two important parameters (neutral temperature and outdoor temperature) in the adaptive thermal comfort model was the focus of this work. A longitudinal survey was conducted from Jan. 2010 to Feb. 2011 in two naturally ventilated office buildings located in Changsha, China. During the survey, the thermal sensation of the subjects was investigated, and the indoor temperature was measured daily. Based on the field data, the neutral temperature and the running mean outdoor temperature were determined. Further, an adaptive thermal comfort model was established by quantifying the relationship between the neutral temperature and the running mean outdoor temperature. The results show that the adaptive thermal comfort model based on the running mean outdoor temperature can well reflect the change of neutral temperature in the two office buildings with the climate of Changsha China. This study provides a reliable method to adjust the adaptive thermal comfort model based on the running mean temperature for Chinese people. [ABSTRACT FROM AUTHOR]

This study investigated the effects of four important microclimate parameters on outdoor thermal sensation and neutral temperature. A long term (almost 2 years) field investigation was conducted at six typical public spaces in Changsha China, with hot-summer and cold-winter climate. During a single investigation of one day (from 9:00 to 18:00), outdoor air temperature, air humidity, global temperature and wind speed were continuously measured at one measuring point. People visiting the public spaces (near the measuring site) were randomly invited to fill out a questionnaire describing their feelings of thermal comfort and other important psychological factors. Based on the field data (7851 samples), relationship between people’s outdoor thermal sensation and the microclimate parameters were quantified. Further, the effect of the microclimate parameters on outdoor thermal sensation and neutral temperatures was analyzed. The results revealed that outdoor microclimate parameters, especially outdoor air temperature, play important roles on outdoor thermal sensation when people stay outdoors. The variation in outdoor microclimate parameters led to the biggest change of outdoor neutral temperature in winter. Seasonal and regional differences in outdoor neutral temperature were found, which reflects different thermal comfort requirements under distinct outdoor microclimate conditions. [ABSTRACT FROM AUTHOR]

Abstract: This study proposed a method to determine time period of thermal adaption for occupants in naturally ventilated building, and analyzed the synergistic and separate feedback effect of the physical and psychological adaption modes on the time period of thermal adaption. Using the method, the values of the time period of thermal adaption were obtained on the basis of the data from a long-term field survey conducted in two typical naturally ventilated offices located in Changsha, China. The results showed that the occupants need to take 4.25 days to fully adapt to a step-change in outdoor air temperature, under the synergistic feedback effect of the physical and psychological adaption modes. The time period of thermal adaption increased to 13 days, if only the feedback effect of the physical adaption mode was accounted for. The difference between the two values of the time period of thermal adaption indicated that the psychological adaption mode can speed up the process of thermal adaption to the variation in the outdoor climate condition. This study presented a new insight into the feedback from the thermal adaption modes to occupant thermal comfort. [Copyright &y& Elsevier]

Clothing adjustment is an essential way for people to adapt to the weather changes and maintain thermal comfort in an outdoor environment. In this study, it was assumed that outdoor clothing adjustment was influenced by the local past temperatures. With temperature changes, clothing adjustment could be divided into "free adjustment phase" and "restricted adjustment phase". Two consecutive years of outdoor field investigation experiments were conducted in 6 typical outdoor spaces in Changsha, China, which was hot in summer and cold in winter. During the field experiment, outdoor thermal environment parameters were measured in real-time, meanwhile, clothing and thermal comfort of participants were documented. The analysis results of field experiment data verified the assumption. 7876 effective samples were collected to build a creative outdoor clothing model (OCM) considering the weather characteristics of Changsha based on running mean temperature and four-parameter logistic function. The determination coefficient (R 2) of the OCM was 0.954, which was higher than the existing models. Moreover, prediction deviations were within 20% for 86% samples. According to the OCM, the range of running mean temperature corresponding to the free adjustment phase was 4 °C–24 °C for the Changsha residents. The free changes of clothing insulation during this phase enabled people to maintain thermal comfort in the outdoor environment. The OCM proposed in this study can provide a theoretical basis for evaluating outdoor thermal comfort and wearing appropriately according to the temperature. ● Clothing adjustment is the most essential means of thermal adaptation outdoors ● Outdoor clothing adjustment is influenced by the local past temperatures ● Clothing adjustment was divided into free and restricted adjustment phases ● A logistic function clothing model was proposed based on running mean temperature ●Clothing adjustment has a feedback effect on thermal comfort in outdoor environment [ABSTRACT FROM AUTHOR]

• A dynamic setting temperature that adapts to climate change was proposed. • The method was based on clothing adjustment behavior which adapts to thermal comfort. • The dynamic setting temperature had significant energy saving potential. • The dynamic setting temperature is useful for intelligent control of air-conditioner. Saving energy consumption of air-conditioning is essential to building energy conservation while satisfying the thermal comfort requirements of indoor environment. On the basis of human clothing adjustment behavior, a dynamic setting temperature (DST) that adapts to climate change was proposed in this paper, i.e. indoor air-conditioning setting temperature changes dynamically with outdoor air temperature; furthermore. A method was established to obtain the DST. The daily mean clothing insulation was predicted according to the historical temperature at first, then indoor thermal comfort temperature was calculated based on the variable clothing insulation, and finally the DST was determined. According to the value or range of predicted mean vote (0, -0.5~0.5, -1~+1) corresponding to the thermal comfort, three levels of DST were defined. The corresponding thermal acceptability rates were 95%, 90% and 73%, respectively. A simulation of DST was conducted in a public building in Changsha, China based on meteorological data of 2017. Three levels of DST ranges were obtained, varied from 20.1 to 27.8 °C in level I, 17.8 to 28.7 °C in level II and 15.4 to 29.7 °C in level III, respectively. The simulation results of operational air-conditioning energy consumption shows that the application of DST could save up to 65.5% of energy consumption compared with the traditional fixed setting temperature (FST), and the operational energy consumption decreased by 59.1% due to the application of level-III DST compared with level-I DST. Therefore, the DST proposed in this paper has significant energy saving potential while meeting the thermal comfort requirements. [ABSTRACT FROM AUTHOR]