| requirements are put forward on more and more thermal environment. Thermal comfort study field also gradually extend to the automotive, aerospace, medical, sports and other areas. Early thermal comfort researches rely on the subjective evaluation and need to undertake a large number of questionnaires, which is not very convenient to application. Practical projects need to judge a large number of various thermal environments, for the sake of convenient application and cost saving, human thermal comfort model are developed. Using thermal comfort model, designers can do designing, adjusting relevant thermal environment, and evaluating the thermal environment and thermal comfort easily, which is very favorable to thermal comfort theory's application.Common human thermal comfort model consists three parts: environment model, thermal regulation model and thermal comfort estimation model, in which the thermal regulation model describe human body thermal properties and modulate physiological processes in thermal environment, and provide real-time various physiological parameters on human body, which is the input parameters of thermal comfort estimation model. Human thermal parameters which are describing human thermal characteristics in thermal regulation model were adopted from early European model reference data. The related formulas of different parameters are still not changed. It found that regional,ethnic and gender differences in human body have great influence on human parameters. By measuring human parameters of Chinese people, the difference between different regions and its effects on mean skin temperature calculation are studied.Structural parameters in thermal regulation model, such as height, weight and others can be measured very easily. But thermal parameters are more difficult to determine, such as thermal conductivity, heat capacity and so on. By comparing several tissue thermal parameter measurement methods, a simple and convenient method for thermal parameter measurement is chosen in this paper. The three point heating method have two parts: heating the middle part of tissue with a constant heating source; three temperature sensors are put on skin to record skin temperature. Tissue thermal conductivity, heat capacity and perfusion rate can be calculated by temperature change rate. At three different temperature : 22℃,25℃and 28℃, 12 subjects(half north and half south) were selected, three parts of the skin temperature were measured. The results of the experimental data found that Chinese thermal parameters have obvious differences. European thermal comfort model can't be used directly to Chinese people. Male's thermal conductivity and specific heat are greater than the female's; thermal parameters had little difference between north people and south people; temperature's influence on thermal parameters is not significant.Skin area distributions have a significant difference between different countries, with can be found by analysis related literatures. In order to study effect of the human body parameter difference on thermal comfort judgment indexes, human skin area of distribution was selected to judging its influence on mean skin temperature. In air conditioning environment, thin film platinum resistance sensor was used to measure human skin temperature. 7 local skin temperature of the 22 subjects were measured at four different air temperature condition ( 21℃, 24℃, 26℃, 29℃). DuBios 7- point method is chosen as the calculation method of mean skin temperature. Using different regions of the skin area ratio as the coefficients of formula to analyse experimental data, mean skin temperature calculation results of three different regions were significant differences. Gender differences have very limited effect on mean skin temperature. Environmental temperature change trend have a significant effect on mean skin temperature and results'accuracy; cooling process can effectively improve the accuracy of the calculated results. |
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