Outdoor Shade Environment, Human Thermal Comfort Survey And Dynamic Thermal Comfort Research

Stable thermal-neutral air conditioning environment, which weakens people's thermal adaptability, does harm to people's health, and at the same time makes people feel dull and tired. Because of these disadvantages of stable ace, people turn to a new air supply pattern-dynamic air supply these years. Dynamic air supply emphasizes thermal adaptability, therefore it is held that proper dynamic condition can not only meet people's demand for health, but also satisfy their thermal comfort.In the area of dynamic thermal comfort, all the scholars focus on the researches of dynamic air supply patterns and strategy , characteristics of dynamic air supply as well as actual investigations under different dynamic condition. However, neither theory nor standard for dynamic thermal comfort is proposed. This study is to make clear the factors which influence dynamic thermal comfort and analysis the effect of these factors on thermal comfort.To study thermal comfort is actually to study how to regulate human himself with the sounding thermal condition: that is how the environment influences human body and how human body influences the environment. All the work on this study centers on these two questions.Through theoretically analysis, heat transfer between human body and the ambient is studied, then effect of body heat storage and thermal adaptability on thermal sensation and thermal comfort is analyzed. It is proposed that both body thermal condition and objective parameters must be considered in dynamic thermal comfort study. Furthermore, it gives the reason why only human body thermal condition is needed under stable condition, which renew people's understanding about thermal comfort. As body temperature is the main response to body thermal condition, the variation regularity of body temperature with environment is also discussed and a simple way to acquire average body temperature is brought out.Both practice and experimental studies of other scholar prove that proper natural experiment can make people feel more cheerful and healthy than typical air conditioning experiment. It is thought that only air supply pattern which simulates nature wind is the best dynamic air supply pattern. In this study investigations on body thermal comfort under outdoor pavilion environment in summer are undertaken, environmental factors which influence thermal sense \draft sense and humidity sense are analyzed, the variation regularity of subjective sense with environment is studied, objective parameter range of subjective sense is given. As air temperature is the most effective environmental factor on thermal comfort, while human body temperature is the most. effective human condition factor, relationship equation about thermal comfort, air temperature and average human body temperature is obtained by regressive method. Then conclusion is made from the equation that people prefer a slightly hotter ambient and cooler body temperature condition. It is the first time to take human body condition and objective condition into human body thermal comfort index as two separate parameters.The study indicates that simulating suitable natural environment can most satisfy people's demand for health and comfort, therefore it is the most ideal dynamic air supplypattern. According to people's demand for thermal comfort, body temperature should be in the range of 35.7 C~36.5 C, air temperature 25.5~30.4 C, wind speed 0.75~1.5m/s, relative humidity is about 60 %. For parameter chosing, indoor environment change should agree with natural climate, which means temperature difference should be reduced as much as possible. Personalized air conditioners which appeared recent years can realize personalized air supply and individual control, make dynamic air supply realizable in project, thus embody the heading direction of" science and technology center on human beings".