| Since the 20 th century,the human body thermal regulation research has been a relatively popular research topic in the fields of aviation,automobile and other heavy industry manufacturing.The human body’s own temperature regulation principle and thermal response prediction have become the focus of attention,and its research results are mainly used as clothing(equipment)thermal comfort,hot and humid environment design and other prerequisites,so that clothing(equipment)can ensure the safety of staff life.First of all,based on the 3D human body finite element heat and moisture transfer model which is close to the real human geometry in the early stage,and combined with the latest research results of phase change materials,items that reflect the heat transfer and thermal regulation of phase change microcapsules are added to the clothing model.Comparing the calculated results with those of ordinary cotton clothing.the conclusions show that the addition of phase change microcapsules in clothing can significantly delay the rate of change of human skin temperature caused by changes in external ambient temperature.Secondly,in order to make up for the deficiencies of the previous model on the geometric structure and blood circulation system,this paper establishes a highly reduced human geometric model and a circulatory system model that takes into account the heat exchange effect between the arterial vascular tree and human tissue.The aortic vascular tree is used to simulate the blood circulation system.Based on the calculation of the cross-sectional area and flow rate of the blood vessel at each moment,the average vascular cross-sectional area and flow rate are obtained by the average method within the cycle.Consistency,and the calculated end blood flow of the internal arterial blood vessels of the human body is substituted for the perfusion blood flow in the traditional model to adjust the tissue temperature.Finally,on the basis of highly reducing the coupling of human geometry and arterial and vascular trees,this paper implements a passive system simulation of tissue’s own metabolic heat generation,heat transfer,and heat exchange with the blood.The core temperature and average skin temperature are used as the basis,and the thermal regulation system of the Stolwijk25 node model is used as the active system to realize the simulation of human body heat transfer and thermal regulation.The overall body temperature distribution,sweat regulation,tremor regulation,and epidermal blood perfusion rate of a naked human body standing at 18°C for two hours and then transferred to an environment with an ambient temperature of 42°C for half an hour were calculated.The time-varying data,and the calculation results of the body temperature distribution are in good agreement with the experimental data published by Stolwijk.The conclusion shows that the model developed in this paper can intuitively obtain the temperature profile of any part inside the real human body structure,and on the basis of retaining the original classic sweating and tremor thermal regulation model,a blood flow model that is more in line with the actual distribution is established,making simulation The prediction data is more accurate,and the calculation results are displayed more clearly,which can be applied to human thermal response research and observation analysis in related fields. |
