火灾环境中人体与热源之间的热交换将破坏机体的热平衡状态，使消防员面临皮肤烧伤风险。皮肤-微环境-消防服系统热质耦合传递模型可用来探索热暴露期间系统中的热质传递机理，预测人体皮肤烧伤的等级与时间。然而，现有模型多忽略人体运动或织物中水分对系统热传递的影响。本文在传统热传递模型的基础上，考虑了人体运动与织物中热质耦合效应，开展了火灾环境下消防员的皮肤烧伤数值模拟。

基于传统热传递模型，考虑人体移动速度、织物运动频率与振幅等人体运动参数和织物中水分的相变、吸附与解吸等传质现象对热传递与皮肤烧伤的影响，建立动态的皮肤-微环境-消防服系统热质耦合传递模型。通过与文献中实验和模拟值的对比验证当前模型的有效性，预测消防服中温湿度分布、皮肤烧伤等级与时间，参数化分析影响皮肤烧伤预测的关键因素。

结果表明：人体皮肤烧伤预测与其运动状态有关。人体运动期间织物周期性运动会引起系统热传递的波动，导致二度烧伤时间提前。此外，当前模型预测的人体中等移动速度下皮肤发生二度烧伤的时间比低、高移动速度下缩短33.3%-35.2%。织物运动振幅与皮肤烧伤存在非线性关系。低移动速度下二度烧伤时间与织物运动振幅负相关，而中高移动速度下织物运动振幅为2.5 mm时，二度烧伤时间较2 mm运动振幅延长12.9%-29.8%。基于系统热质耦合模型预测的闪火条件下着装人体的皮肤温度与实验值的最大误差仅为3.79%。通过当前模型分析了皮肤烧伤的影响因素，结果显示皮肤发生二度烧伤的时间随隔热层厚度、热源温度与织物密度的增加分别延长10.9s、33.5 s与8.9 s。此外，较小的微环境厚度使得高温织物周期性接触人体皮肤，导致二度烧伤时间大幅缩短，增加了消防员的皮肤烧伤风险。当前研究结果可为准确评估灭火救援期间消防员的热安全状态与消防服的性能优化提供基础数据与理论支撑。

Firefighters are usually exposed to thermal radiation during firefighting. The heat balance of the body is disrupted by heat exchange between the human body and the heat source and it put firefighters at risk of skin burns. The coupled heat and mass transfer model of skin-microenvironment-firefighters’ protective clothing system can be used to explore the heat and mass transfer mechanism during the heat exposure of system, and predict the degree and time of human skin burns. However, the effect of moisture and human body movement on the heat transfer of the system has been neglected in previous models. Based on the traditional heat transfer models, this study considers the coupling impact of heat and mass transfer in fabrics and human body movement, and carries out numerical simulation of skin burns of firefighters under fire environment.

Based on the traditional heat transfer model, the dynamic heat and mass coupled model of skin-microenvironment-firefighters’ protective clothing system was established by considering the influence of the human movement parameters such as human body movement speed, fabric movement frequency and amplitude, and the mass transfer phenomena such as phase change, adsorption and desorption of water in fabric on heat transfer and skin burns. The validity of the current model was verified by comparing experimental and simulated values with those in the literature, and predicted the temperature and humidity distribution in the firefighters’ protective clothing, skin burn degrees and times , and parametrically analyzed the key factors affecting skin burns.

The results show that the prediction of skin burns is related to human body movement status. The fluctuation of heat transfer in the system is caused by the movement of the fabric during the human body movement, leading to an earlier time to second degree burn. Moreover, the time to second degree burn was 33.3%-35.2% shorter at medium human body movement speed than at low and high movement speeds. There is a nonlinear relationship between fabric movement amplitude and skin burns. At low movement speed, the time to second degree burn was negatively associated with fabric movement amplitude, whereas it was delayed by 12.9%-29.8% at the fabric movement amplitude of 2.5 mm at medium and high human body movement speeds. The maximum error between the skin temperature predicted by the heat and mass coupling model of system and the experimental value in the literature was only 3.79%. The factors influencing skin burns were analyzed by the current model, and the results showed that the time to second degree burns increased by 10.9 s, 33.5 s and 8.9 s with the increase of thermal liner thickness, heat source temperature and fabric density, respectively. The smaller thickness of the microenvironment made the high-temperature fabric periodically contact the human skin, resulting in a significant reduction in second degree burn time, and increasing the risk of skin burns to firefighters. The current model provided basic data and theoretical support for the thermal safety state of firefighters during firefighting and the performance optimization of firefighters’ protective clothing performance.