Modeling Of Heat And Moisture Transfer Of Two Kinds Of Protective Clothing And Inverse Problems Of Parameter Determination

In this paper,we establish mathematical models of heat and moisture transfer for warm clothing under low-temperature and firefighting protective clothing under high-temperature flame,respectively,and give the numerical methods for solving the models.Based on this,we propose the inverse problems aiming at meeting the thermal comfort for warm clothing and the inverse problem aiming at protecting human body from skin burn and extending working hours for fire protective suits.We also give the algorithm for solving inverse problems.The main contributions of this paper are as follows:Firstly,we establish a mathematical model for heat and moisture transfer of multilayer clothing under cold-temperature environments and provide corresponding boundary conditions.The model is a coupled system of ordinary differential equations.We first prove the existence and the uniqueness of the solution by using the fixed point theorem,and then give the numerical method for solving the model.In accordance with the thermal comfort index of clothing and the Monte Carlo statistical approach,we propose inverse problems with the maximum probability of falling within the comfort index interval determined by thicknesses of multilayers as the objective function and the maximum probability of falling within the comfort index interval determined by porosities of multilayers as the objective function.Then,we solve problems by using the particle swarm optimization algorithm.Finally,numerical simulation is given and the solutions verify the rationality of the inverse problems and the effectiveness of the algorithm.This study provides a theoretical basis and guidance for the design of warm clothing.Considering heat radiation,heat conduction,and phase change of water,we construct a seven-layer heat and moisture transfer mathematical model of human body-clothingenvironment system under hot-temperature,and the model is discretized by using the finite difference method.We study the heat and moisture distribution of fabrics with four different combinations of outer shell,moisture barrier and thermal liner of firefighting clothing.Based on this,taking into account the significant influence of the air gap on heat and moisture transfer,and with the assumption of ensuring the safety of the human body,air gap thickness determination inverse problem is proposed with the goal of maximum work time.And particle swarm optimization is used to solve the problem.This study provides technical support for the performance evaluation of firefighting protective clothing.