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

The design of functional clothing is mainly based on people's requirements for cloth-ing's warmth,safety,radiation protection,and compressive performance,according to the physical laws of heat and moisture transfer inside the fabric,and establishes a reasonable mathematical model to optimize the parameters of the clothing and meet the functional requirements.Firstly,this paper studies the heat and moisture transfer model in fireproof clothing under high temperature and high humidity environment,and combines human body burn model to predict the time when human skin reaches all levels of burn.Based on the direct problem model,we propose an inverse problem of the optimal decision of fireproof clothing material parameters.According to the proposed inverse problem,we construct the corresponding optimal objective functional and solve it numerically.In addition,considering the heat and moisture transfer model in the three-layer textile material under low tempera-ture conditions,and according to the purpose of the best thermal and moisture permeability in clothing,we give the inverse problems of three-layer textile thickness determination and porosity determination,further more,we construct the corresponding objective functional and solve it by intelligent method.This paper is mainly composed of the following parts:The first chapter introduces the research background and significance of functional clothing at home and abroad,and brie.fly summarizes the research conte.nt and result,s of this paperIn the second chapter,at first,considering the effect of water in the external environ-ment on heat transfer in fireproof clothing,the mathematical model of heat and moisture transfer in fireproof clothing-air layer-human skin system is established by adding the mois-ture transfer equation on the basis of the existing heat transfer model.The reasonable initial boundary value conditions between corresponding layers are given,and solving the model by the finite difference method,the distribution of temperature and water vapor concentration in each layer of fireproof clothing is also obtained.Secondly,combining the heat and mois-ture transfer model with Henriques skin burn model to predict the time when human skin reached various burns by calculating burn integral value.Numerical simulation results show that a certain amount of moisture transfer can effectively slow down the rate of temperature rise in clothing and human skin and delay the occurrence of skin burns at all levels.Finally,based on the model of direct problem of fireproof clothing and the model of skin burn,to en-sure that the human skin does not burn,and to maximize the working time of firefighters in high temperature and high humidity environment,the inverse problems of fireproof clothing material parameter determination are proposed,and the corresponding optimization model is established and solved numerically.In the third chapter,improving the existing mathematical model of heat and mois-ture transfer of three-layer textile under low temperature conditions,the original first type boundary conditions are improved to the third type of boundary conditions.The finite dif-ference method is used to discretize the model and solve it numerically,we also analyze the existence and uniqueness of solutions to direct problem.On the basis of the direct problem,we propose the inverse problems of three-layer textile thickness determination and porosi-ty determination,give the optimal objective functional expression,and solve it by genetic algorithm.The fourth chapter summarizes the main research content and innovation,and points out the direction of the further research.