Sensitivity of Temperature Field to Material Parameters within the Clothing Laminate Process

Textile laminate is created by introducing a thermoplastic polymer between the inner layer and outer material, which is then softened by heat. The connection is secured by adhesive properties of the polymer and the pressure applied after the heating zone. The state variables are defined as thus: the temperature of the heating zone and the pressure of rollers for the pressure system. The heat problem is described by the heat transport equation as well as the boundary and initial conditions. The distributions of the mean temperature within the polymer layer can be determined by numerical simulation. The sensitivity of the temperature field to the selected material parameters within clothing laminates is determined

Numerical analysis of free folding of flat textile products and proposal of new test concerning bending rigidity

Free folding of flat textiles has been studied by means of elastica for the same shape and folding conditions across the product. Elastica is described using the system of six first-order differential equations accompanied by a set of boundary conditions. The problem is solved by the shooting method and divided in two stages. The shooting method is ineffective for some parameters, and the process is divergent which is clarified by sensitivity analysis. The proposal adopts the width of fold as a measure of bending stiffness (C) and the sample is now subjected to bending in both directions in a wide range of curvatures. This is alternative to the Peirce’s test, in which the test specimen is subjected to a slight bending in one direction only. The Peirce’s test gives the unprecised results under some loadings. This study presents a detailed sensitivity analysis of some process parameters to describe the unique solution for bending problem of textiles. It is also proposition for new test for bending rigidity of textiles

Wybrane zagadnienia z metrologii użytkowej odzieży funkcjonalnej

Politechnika Łódzka. Wydział Technologii Materiałowych i Wzornictwa Tekstyliów. Katedra Materiałoznawstwa, Towaroznawstwa i Metrologii Włókienniczej.Lodz University of Technology. Faculty of Material Technologies and Textile Design. Department of Material and Commodity Sciences and Textile Metrology.Rozwój technologii nowych materiałów, sposobu ich przetwarzania i wykorzystywania, a także coraz lepsze poznanie mechanizmów zachodzących w organizmie człowieka sprzyjają rozwojowi odzieży specjalnego przeznaczenia. Odzież już nie stanowi wyłącznie bariery przed zimnem, ale również ma za zadanie stanowić barierę przed czynnikami szkodliwymi, skrajnymi warunkami termicznymi, a także wspomagać funkcjonowanie organizmu jej użytkownika w warunkach ekstremalnych. Obecnie coraz większą uwagę zwraca się na zachowanie optymalnych warunków, w jakich powinien żyć i pracować człowiek, ponieważ zostało potwierdzone, że manualne i intelektualne zdolności człowieka osiągają swoje optimum w warunkach komfortu cieplnego. W tym kontekście problem odzieży ochronnej zapewniającej optymalny komfort cieplny użytkownika nabiera szczególnego znaczenia.Prace badawcze do prezentowanej książki były współfinansowane z Projektu pt. „Optymalizacja struktury ubioru ochronnego dla noworodków urodzonych przedwcześnie przy zastosowaniu oryginalnych narzędzi wspomagających proces projektowania” UMO-2011/03/B/ST8/06275, finansowanego przez Narodowe Centrum Nauki i Projektu pt. „Nowoczesne ochrony osobiste służb ratowniczych KSRG w oparciu o potrzeby użytkowników końcowych”, O ROB 0014 01/ID14/1, finansowanego przez Narodowe Centrum Badań i Rozwoju oraz z prac statutowych Wydziału Technologii Materiałowych i Wzornictwa Tekstyliów, Politechniki Łódzkiej

CMM-2011 -Computer Methods in Mechanics Sensitivity oriented shape optimization and identification during opposite coupled diffusion within composites

Abstract The special structures of textile dressings contain the therapeutic substance in microcapsules. The diffusion of the activating agent (the exudate from the wound) through the material initiates the chemical reaction within microcapsules and releases the therapeutic agent. The semi-permeable membrane on the surface reduces the diffusion of therapeutic agent to surrounding, whereas the exudate diffuses normally. The oppositely directed coupled diffusion is analyzed within 2D cross-section of dressing. State variables are both activating agent concentration and therapeutic substance concentration. State equations, boundary and initial conditions are determined. The sensitivity of an arbitrary functional is analyzed by means of direct and adjoint approaches and implemented into the problem of shape optimization. Numerical example of 2D shape optimization is presented

Optymalizacja warunków sprężonego przewodzenia ciepła i masy w wyrobach włókienniczych

Red. serii Monografie : Wodziński, PiotrThe coupled heat and mass transport is very common physical phenomenon within the diff erent textile structures. Thus, the heat and mass are transferred from the heat and mass sources through the multilayer composite structure to the surrounding. The most frequent are the transient problems whereas some of them can be defined as the steady heat and mass transport. The problems are formulated in generał form and the analysis of the specific case can simplify the model introduced. Of course, each coupled problem can be analyzed independently and the models are completely different. First, the physical model of the coupled heat and mass transport was introduced. The typical homogenization methods were defined and its characterized. The number of analyzed dimensions was discussed as the result of geometry and transport conditions within the multilayer textile composite. The structure is described by means of the state variables, which are: the water vapor concentration within fibres, the water vapor concentration within the free spaces between fibres and the temperature. The mathematical model was determined by means of the heat and mass balances. The third equation introduced is the practical correlation concerning the parameters of the water vapor transport. The coupled problem is sensitivity oriented and the first-order sensitivity is defined as the materiał derivative of an arbitrary behavioral functional with respect to the design parameters. The sensitivity can be analyzed by means of the direct and adjoint method. The results are the state equations, the set of boundary and the initial conditions for the additional system associated with each design parameter (the direct method)/the adjoint system (the adjoint method), as well as the first-order sensitivity correlations. Next goal is to define the optimization problem and formulate the optimality conditions. Thus, the variational formulation of the Finite Element Method was used. It means that the optimization functionals should have the elear physical description. The most used are consequently defined. The practical implementation of the analysis performed is the numerical optimization of the transport conditions within the textile dressing with the microcapsulated pcm-material. The oppositely directed diffusion is described by the exudate transport from the wound to the surrounding and the transport of the therapeutic agent from the microcapsules to the skin. The second numerical example is the textile geomaterial which drain the earth structures and transports the water to the surrounding. Finally, the conclusions and the expected future trends are given

Numerical Optimisation of Thickness of Composite Bonnet for Neonates

Head is the most sensitive body part of neonate. Head that is considerably uncovered causes the significant heat and moisture loss from the skin to the surrounding areas. The main goal is to optimise the thickness of a multilayer composite textile bonnet to secure the optimal skin parameters. Problem is solved using both sensitivity analysis and material derivative concept. An arbitrary objective functional is introduced, its first-order sensitivity is formulated by means of a direct approach. Numerical application is the thickness optimisation of a composite bonnet made of different textile materials

Wpływ pokrycia włókienniczego na charakterystyki aerodynamiczne skrzydła paralotni

Defined herein are the two PA-fabrics covering a paraglider wing, with the comparative object being permeable clothing material. The material parameters of textiles are applied in numerical simulations of aerodynamic characteristics using the program ANSYS. The state variable is the pressure within the airfoil profile. The space model of a paraglider wing and plane model of its cross-section in the symmetry plane are analysed. The model was approximated by the coordinates of crucial points and smoothed by the spline-curves. The visualisation of stream filaments shows that it is advisable to cover the wing with the impermeable fabric.W pracy zdefiniowano dwie tkaniny pokrycia skrzydła paralotni wykonane z poliamidu, obiektem porównawczym był przepuszczalny materiał odzieżowy. Parametry materiałowe tekstyliów zastosowano w symulacjach numerycznych charakterystyk aerodynamicznych z wykorzystaniem programu ANSYS. Zmienną stanu było ciśnienie w profilu skrzydła. Analizie poddano przestrzenny model skrzydła paralotni i płaski model jego przekroju poprzecznego płaszczyzną symetrii. Model został przybliżony przez współrzędne punktów węzłowych i wygładzony za pomocą krzywych typu spline. Wizualizacja strug elementarnych pokazała, że celowe jest pokrywanie skrzydła tkaniną nieprzepuszczalną

Globální transport tepla a hmoty v systému: pokožka novorozence – textilní kompozita – okolí

Globální model transportu tepla a hmoty je definován tepelnou rovnováhou při změně hmoty během odpařování potu z těla. Teplo je vytvářeno metabolickou produkcí tepla a ztrácí se vlivem různých jevů. Podmínky pro zajištění nezbytných parametrů těla novorozence jsou řešeny globálně pro různé parametry dětské čepičky a vrchního oblečení. Studie se zabývá různými možnostmi, jak zabránit hypertermii a hypotermii

Tests of applications of transfer films in seams lamination technology

The main goal of the article is to investigate the replacibility of sewn stitches by laminated seams in cotton clothing products. The research objects are seams prepared experimentally in industrial conditions, laminated with thermal transfer film in the form of tape. There are determined (i) the lamination parameters on thermal press influencing the quality index of created seams, (ii) the effect of laminated seams on the aesthetic properties of the product. The permissible values of the quality index are compared for laminated and sewn seams. Hence, we conclude that the selected sewn seams can be replaced by laminated structures