| People's demand for indoor thermal environment comfort rises as the economy develops and their living standards improve. This heightened demand for indoor thermal comfort in turn increases building energy consumption. Challenged by the serious global energy crisis and climate change, the sustainable development of Chinese buildings relies heavily on the realization of healthy, safe and comfortable indoor environments while also achieving energy savings and reduced emissions. After describing a comparative analysis of stable and dynamic environments, this thesis emphasizes researching building indoor dynamic thermal comfort from the perspectives of both human health and energy efficiency. It also argues that research on dynamic thermal comfort should integrate research on objective physiological reactions and local climate conditions. The thesis employs this approach in a case study of Chongqing, P. R. China.Most studies of thermal comfort in dynamic environments to date exclusively have focused on human subjective sensation instead of objective physiological reactions. The author conducted a questionnaire survey of office building indoor thermal environments in over 10 districts and counties of Chongqing during the summer and winter of 2007 to understand the following: the current indoor and outdoor thermal environments in Chongqing during the winter and summer, human self-adapting behaviors which respond to thermal environmental change in indoor environments lacking air conditioning, and people's satisfaction assessments of thermal environments. The results show that Chongqing residents posses nearly identical habits of dress, and their assessments of indoor environments in similar indoor thermal environments and attire also tend to be the same. Based on these findings, the author conducted another field test and questionnaire survey, this time in downtown Chongqing office buildings and residential buildings during the four seasons in a cycle from August 2008 to September 2009. The data statistics and analysis indicate that for indoor environments without air conditioning, when the outdoor temperature is 12°C to 36°C, the indoor temperature increases as the outdoor temperature rises; when the outdoor temperature is below 12°C, the indoor temperature remains above 10°C. There maintains a difference of approximately 2°C between the outdoor and indoor temperatures. The thermal resistance of clothing decreases as the indoor temperature rises. The thermal resistance of clothing is from 0.2clo to 0.4clo when the indoor temperature exceeds roughly 28°C. When the indoor temperature is below approximately 14°C, the thermal resistance of clothing is 0.9clo～1.84clo. These results indicate that people are accustomed to adding clothes in cold environment to achieve comfort. Air velocities increase as the indoor temperature rises. The air velocity is between 0 and 0.2m/s when the indoor temperature is low; air velocity can reach up to 1 m/s when the indoor temperature exceeds 28°C.Based on the above analysis and to identify parameters reflecting the influence of the thermal environment on human body comfort (parameters such as body temperature adjustment, the perspiration mechanism, the cardiovascular system, and the nervous system), the author conducted a questionnaire survey of subjective feelings, completed field testing, and carried out a human physiology experiment in the laboratory. The significance analysis conducted on more than 10 parameters, including body temperature, skin temperature, skin impedance, electrocardiogram, heart rate, blood pressure, sensory nerve conduction velocity (SCV), motor nerve conduction velocity (MCV), testing point skin temperature, Electrocardiograms (EEG), confirmed that the parameters to be analyzed in the subsequent research phase included SCV, MCV, testing point skin temperature, and average skin temperature.The following results were obtained in the succeeding phase that was designed to discover the changing rules of these selected parameters under different thermal environments: in low winter temperatures, the SCV and Tskin-SCV decrease as the time length of stay extends; when exposure time exceeds one hour, the change of physiological parameters tends to be more gentle, which is attributable to the limits of the human body's capacity for self-adaptation to thermal environments and was evidenced by the nasal drainage of some subjects. The analysis established that this parameter change can be avoided when the indoor temperature exceeds 16°C. Based on the results of the human subjective sensation questionnaire survey, it is found that when the time length is extended, parts of the body, such as the hands and feet, experience discomfort. Therefore, it is concluded that the indoor temperature should not be lower than 16°C in winter if people must remain indoors for more than one hour and they are wearing normal attire.To confirm the highest acceptable temperature in summer, the author also conducted testing on skin surface temperature change for various durations which people remained indoors in artificial climate environments of 26, 27, 28 and 29°C, respectively. The data analysis shows that when people sit inside without any movement while wearing clothing with thermal resistance of approximately 0.3clo, and the relative humidity is 70% and the air velocity is about 0.05m/s, the indoor temperature should not exceed 28°C. If the thermal resistance of the clothing rises or the relative humidity increases, the highest acceptable temperature decreases.Analysis of the influence of mechanical ventilation on human comfort under high summer temperatures shows that, when the thermal resistance of clothing is approximately 0.3clo, and the comparative humidity is around 70% and the air velocity is increased to about 1m/s, the upper limit of indoor acceptable temperature can be 30°C, 2°C higher than under conditions when mechanical ventilation is not operating.Therefore, using subjective questionnaire survey and objective lab experiment methods, and after obtaining data statistics and completing analysis, this research confirms the 80% and 90% indoor acceptable temperature range for Chongqing environments lacking air conditioning in all seasons, and has determined the typical temperature and humidity scope when people are normally attired, and obtained the indoor temperature scope for winter and summer. These findings provide effective methods to conduct assessment research on indoor thermal comfort.This thesis shows the acceptance range for indoor thermal environments of people inside residential and office buildings and the corresponding change of clothing thermal resistance indoors. It is proposed that human physiological parameters such as SCV, MCV, testing point skin temperature, and average skin temperature can reflect the influence of the thermal environment on human physiology effectively. Moreover, through extensive laboratory experimentation on human physiology and human body comfort, and in combination with field testing and questionnaire surveys, the changing rules of these parameters as environment changes have been identified, the scope of indoor acceptable temperature as outdoor temperature changes in all seasons has been confirmed, providing a basis for indoor thermal comfort assessment in environments lacking air conditioning.
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