Prediction and improvement of human heat stress based on numerical model

With the rapid progress of global warming and urbanization, the frequency of extreme high temperature weather has increased significantly around the world. In this context, groups at high risk of direct exposure to extreme heat are often at risk of life-threatening diseases caused by high temperature environments. Whether it is located in the airport south of the Yangtze River or in the northeast, during the hot season, the pilot's walking on the ground before boarding and the cabin prep-aration process are subjected to high temperature. Although a variety of numerical models have been developed to predict human heat stress, and personal cooling garment (PCG) has been designed to reduce the level of human body heat stress in extreme or indoor working environments, but the quantification of the actual cooling efficiency of PCG into the numerical model of human heat stress prediction is still a relatively weak link in the field of research. Specifically, most of the current studies focus on the independent evaluation of PCG cooling performance or the use of models to predict heat stress, and few organic combination of the two for comprehensive quantitative analysis. Therefore, the quantitative application research on PCG cooling effect in human heat stress prediction model is of great significance for improving human thermal protection ability and ensuring life safety. Based on this, this paper constructs a numerical model for predicting and improving the level of human heat stress in extreme thermal environments. The heat stress level is calculated and analyzed for two typical scenarios-the extremely heavy work in extreme thermal environment and the work of the crew in the failure environment of the cabin ventilation system, and the effects of PCG with different cooling power on human heat stress levels are discussed. The results show that the model can accurately predict the level of human heat stress under different scenarios, and PCG has a significant effect on alleviating heat accumulation, providing an effective means for the safety protection of work in extreme thermal environment.