Numerical study of human thermal comfort in changing environments of high and low temperature.

A great temperature difference (GTD) in changing environments has a great impact on human comfort and health. Thus, the optimization of human comfort in the GTD environment becomes extremely important. In this paper, the human thermal regulation and clothing heat transfer in the GTD environment were simulated. The predicted skin temperature was verified by the experimental results in the GTD environment. The absolute error percentage of skin temperature was less than 5 %, indicating that the model has good accuracy for prediction of skin temperature in the GTD environment. Influencing factors of thermal comfort in the GTD environment were studied by the validated model. It was found that the influence of clothing thermal resistance had a critical value on the thermal comfort. When the effective thermal resistance was less than the critical value, increasing clothing thermal resistance improved the thermal comfort, and vice versa. The influence of metabolic equivalent change on the thermal comfort in a low-temperature environment was greater than that in a high-temperature environment. Finally, the thermal comfort time of human was predicted by the model, which could predict the duration of thermal comfort state under different GTD environments. The findings have great significance to adjust the comfortable dress of human under the GTD environment. • A numerical model on thermal comfort of dressed body was developed. • The numerical model was comprehensively validated with human trials in GTD environments. • Influencing factors of thermal comfort in GTD environments were analyzed. • Thermal comfort time under various GTD environments was predicted. [ABSTRACT FROM AUTHOR]