Designing thermal protective workwear with autonomous life support system

Abstract

Purpose. The purpose of this study is to provide scientific and experimental substantiation of the principles for designing effective thermal protective special clothing (TPSC) equipped with an utonomous life support system, based on the integrated mplementation of passive and active thermal rotection methods under conditions of extreme and ultra-high temperature exposure. The research is aimed at establishing thermophysical regularities of heat transfer within multilayer material assemblies and developing a predictive model for temperature distribution and protective performance time under convective heat
removal conditions.
Methods. The research methodology is based on a combination of theoretical modeling, experimental
determination of thermophysical characteristics, and engineering design approaches. The theoretical
framework relies on the theory of non-stationary heat transfer and the method of regular thermal regime, employing analytical solutions of differential equations describing heat conduction and convective heat exchange processes in porous multilayer systems. The thermophysical parameters of aterials and material assemblies were determined using a flat bicalorimeter and a regular regime rocalorimeter. The study encompassed material packages omposed of metallized heat-reflective outer layers, heat-esistant fabrics, membrane materials, thermal nsulation interlayers, and lining materials. In addition, a nanostructured textile material modified with silver nanoparticles synthesized via a green echnology approach was developed and mplemented as a hygienic underwear layer. A comparative analysis of various package configurations was conducted in order to identify optimal combinations according to thermal resistance, density, and ergonomic performance criteria. Results. It was established that the exclusive use of passive thermal protection under ultra-high temperature conditions is ergonomically inefficient due to the necessity of significantly increasing garment thickness and mass. The integration of an active convective cooling system ensures a ubstantial increase in the effective thermal resistance of the multilayer structure. A mathematical model describing temperature distribution within a porous thermal insulation layer under forced air filtration conditions was developed. An efficiency coefficient of active thermal protection was introduced and analytically determined, enabling quantitative
evaluation of cooling system performance. xperimental results confirmed that optimized aterial packages incorporating metallized outer layers and advanced thermal insulation materials provide enhanced thermal resistance while maintaining acceptable weight and dimensional characteristics. The application of the nanomodified textile material in the inner layer ensures compliance with hygienic requirements, ultraviolet radiation protection, and improved environmental sustainability of the production process. Scientific novelty. For the first time, a comprehensive physical model of heat transfer in thermal protective clothing combining passive multilayer thermal insulation with active convective cooling has been theoretically substantiated. An analytical solution to the problem of temperature distribution within a porous thermal insulation layer under convective filtration conditions was obtained, enabling determination of the heat flux penetrating toward the human body as well as calculation of the efficiency coefficient of active thermal protection. The approach to the classification of heat-resistant materials according to their thermophysical characteristics and functional role within multilayer assemblies has been further developed. The use of a nanostructured textile material containing silver nanoparticles synthesized through an environmentally safe method is proposed as an integral component of combined thermal protection systems. Practical significance. The obtained theoretical relationships and experimental results provide the possibility of predicting the protective performance time and ergonomic characteristics of thermal protective special clothing at the pre-design stage. The developed design principles contribute to the creation of competitive, high-technology products intended for fire-rescue units and professionals operating under extreme temperature conditions. The implementation of nanomodified textile materials enhances the hygienic properties of garments, ensures ultraviolet rotection, reduces energy consumption in the manufacturing process, and improves the environmental safety of the technology. The proposed approach establishes a methodological foundation for the further evelopment of adaptive and autonomous life
support systems in the design of modern protective clothing.