Mathematical Modeling Of Heat Transfer Within Thermal Protective Clothing And Inverse Problems Of Parameters Determination

The design of the thermal protective clothing aims to get insight law of thermodynamics within textiles by mathematical methods,which could provide theoretical support.The thermal protective clothing is widely-used functional clothing.At present,the research of thermal protective clothing design focuses on thermal protective performance measurement,mathematical modeling of heat transfer within thermal protective clothing,and the development of method and device about testing the thermal protective performance,evaluation of the thermal protective clothing performance and so on.It is important to give reasonable evaluation of the thermal protective performance,which could reduce the thermal damage on the skin.In this article,we mainly talk about the heat transfer model about single layer of fabric.Moreover,after studying the heat transfer model of air gap and skin,we present the corresponding inverse problems according to thermal injury criterion.The main contents are concluded as follows:In chapter 1,we introduce the background and significance of studying thermal protective clothing.The results of previous research and the content of this paper are briefly described.In chapter 2,we introduce the process of mathematical modeling of heat transfer within thermal protective clothing.we analysis the heat conduction and radiation mechanism of thermal protective clothing.The thermal conductivity and the specific heat of Nomex are changing with temperature,according to these,empirical equations for describing the change are deduced.we also analysis the boundary conditions between the fabric and heat source.Based on the analysis above,we present the heat transfer model of thermal protective clothing.Numerical simulation and calculation are given,the results have compared with certificated model proposed by Torvi,which show the effectiveness of the proposed model.In chapter 3,considering the mathematical modeling of heat transfer within thermal protective clothing,we combine it with air gap and the skin's heat transfer model,forming a complete “Thermal protective clothing-Air gap-Skin”system.The effect of the air gap model between thermal protective clothing and the skin in heat transfer is studied numerically.Moreover,mathematical modeling of heat transfer within epidermis,dermis and subcutaneous tissue are also analyzed.At last,we give an initial numerical result of the heat transfer system.In chapter 4,for the design of thermal protective clothing,the aim of inverse problems of parameters determination is to minimize or make no damage on the skin.we focus on the analysis of the system “Thermal protective clothing-Air gap-Skin”,the basal layer(the contact surface of the epidermis and the dermis)is the target we focused on,which should not reach the second degree damage.Based on this,we design a reasonable formulation of inverse problem.Some numerical results of inverse problems are given.In chapter 5,we introduce a TV-like algorithm to recover the initial value of a parabolic equation.In order to solve the minimization function,we introduce the variational adjoint method combined with TV-like regularization.The existence,uniqueness and stability estimate for the regularization problem is analyzed in this part.We also give some examples to show the effectiveness of the method.In chapter 6,as a final chapter,we conclude the innovation in the dissertation and present some inspiring research topics in the near future.