Search results

This paper aims to investigate the comfort properties of modern functional clothing, such as moisture and heat transport. Transport properties are evaluated for real barrier membrane clothes for sport application, under real weather conditions in Middle Europe.

The different combination of functional clothing, with barrier membrane, were investigated under different temperatures and relative moistures inside and outside clothing layers. Water vapour permeability was measured under the steady‐state conditions, by sweating guarded‐hotplate test.

This paper describes the theoretical analysis of moisture transport, and its influence on thermal conductivity; the paper investigates various barrier fabrics for sport apparel, and their ranges of water vapour transport ability under real weather conditions.

All received results are based on the transport of water vapour through a semi‐permeable membrane and are supposed to be conducted mainly within a process of diffusion.

This paper is focused on the theoretical analysis of transport by diffusion of water vapour through porous semi‐permeable barrier textile material, and evaluates the real possibilities for sport applications. The level of transport is limited and mainly depends on the difference of the partial pressures of water vapours outside and inside the porous clothing material.

The phenomenon of heat and moisture transport through porous textile media is a natural problem encountered in real life and has been studied over years by many researchers. However, since the flow rate of moisture diffusing through a clothing fabric is too small to be measured directly, the measurement is usually indirect and the interaction between thermal and moisture transport is not considered.

A mathematical model was introduced in this study to describe the moisture migration and thermal transport through porous textile materials to evaluate the thermal clothing comfort and the interaction between heat and moisture transportation. Heat and mass transportation parameters and the distribution of moisture and temperature within porous textiles are mathematically derived based on the energy and moisture conservation equations during the transportation. In addition, an experimental principle is established to simultaneously measure four moisture and thermal coefficients introduced in this study.

Clothing must also assist the body’s thermal control function under changing physical loads in such a way that the body’s thermal and moisture management is balanced, and a microclimate is created next to the skin. One of the factors which affect moisture transport in a fabric is a fibre type. Hence, the purpose of this paper is to blend the natural hollow and low density fibre, milkweed, with cotton fibre at different proportions and to analyse and compare the influence of milkweed blend proportion on moisture management properties of rotor yarn fabrics with 100 per cent cotton fabric.

In the present study, cotton/milkweed blended rotor yarns were produced by using S-4 cotton variety and milkweed fibres in three different blend proportions such as cotton/milkweed 80/20, 60/40 and 40/60 along with 100 per cent cotton yarn with yarn count of 20 Ne. The single jersey knitted fabrics were produced with similar constructional parameters and then the fabrics were then scoured, bleached and neutralised as per the standard procedure. The fabrics have been analysed for its various moisture management properties using moisture management tester (MMT) and are statistically analysed.

The results indicate that, all the C/M blended fabrics have been classified as “moisture management fabric” and 100 per cent cotton fabric has been classified as “Fast absorbing and Quick Drying Fabric”. The overall moisture management capacity of C/M 40/60 fabric is excellent and could be used for summer, active and summer wear applications. One-way ANOVA analysis carried out at 95 per cent confidence level showed that the results are statistically significant. The pair-wise strength and association between various moisture management indices was analysed using Pearson correlation coefficient and observed that OWTC and OMMC was found to be positively and linearly related to each other.

The authors are confident that the cotton/milkweed blended yarns can be used as an inner wear and sportswear applications owing to the higher moisture regain and hollowness of milkweed fibre combined with the low packing density of C/M blended yarns which leads to overall improvement in moisture management properties of fabrics.

Perspiration and heat are produced by the body and must be eliminated to maintain a stable body temperature. Sweat, heat and air must pass through the fabric to be comfortable. The cloth absorbs sweat and then releases it, allowing the body to chill down. By capillary action, moisture is driven away from fabric pores or sucked out of yarns. Convectional air movement improves sweat drainage, which may aid in body temperature reduction. Clothing reduces the skin's ability to transport heat and moisture to the outside. Excessive moisture makes clothing stick to the skin, whereas excessive heat induces heat stress, making the user uncomfortable. Wet heat loss is significantly more difficult to understand than dry heat loss. The purpose of this study is to provided a good compilation of complete information on wet thermal comfort of textile and technological elements to be consider while constructing protective apparel.

This paper aims to critically review studies on the thermal comfort of textiles in wet conditions and assess the results to guide future research.

Several recent studies focused on wet textiles' impact on comfort. Moisture reduces the fabric's thermal insulation value while also altering its moisture characteristics. Moisture and heat conductivity were linked. Sweat and other factors impact fabric comfort. So, while evaluating a fabric's comfort, consider both external and inside moisture.

The systematic literature review in this research focuses on wet thermal comfort and technological elements to consider while constructing protective apparel.

The purpose of this paper is to develop a method for predicting the chloride ingress into concrete structures, with an emphasis on the low temperature range where freeze-thaw cycles may cause damage.

The different phenomena that contribute to the rate and amount of transported chlorides into concrete, i.e., heat transfer, moisture transport and chloride diffusion are modeled using a two-dimensional nonlinear time dependent finite element method. In modeling the chloride transport, a modified version of Fick’s second law is used, in which processes of diffusion and convection due to water movement are taken into account. Besides, the effect of freeze-thaw cycles is directly incorporated in the governing equation and linked to temperature variation using a coupling term that is determined in this study. The proposed finite element model and its associated program are capable of handling pertinent material nonlinearities and variable boundary conditions that simulate real exposure situations.

The numerical performance of the model was examined through few examples to investigate its ability to simulate chloride penetration under freeze-thaw cycles and its sensitivity to factors controlling freeze-thaw damage. It was also proved that yearly temperature variation models to be used in service life assessment should take into account its cyclic nature to obtain realistic predictions.

The model proved promising and suitable for chloride penetration in cold climates.

Air permeability of ceiling linings is an important element in understanding air and moisture flux from living spaces into the roof cavity. Ideally, these two spaces are decoupled to avoid transportation of moist indoor air into the attic space, where it can lead to condensation on the cold roof cladding. The purpose of this paper is to experimentally characterise the air permeability of a variety of common ceiling types. The results are given as leakage functions. Characteristic leakage data are also given for several ceiling penetrations. A case study illustrates the relevance of these data.

A specially designed test facility allows the installation of different ceiling types of up to 38 m² in area. Laminar flow elements are used to measure the volumetric flow across the ceiling while recording the pressure difference. The experimental data are fitted to the leakage function equation Q =c (ΔP)ⁿ. Ceiling penetrations are characterised in a similar way. For the case studies estimating the transport of moisture into the roof cavity, indoor climate data have been obtained using humidity and temperature sensors.

Air leakage functions are given for a number of common ceiling linings and ceiling penetrations. These data can be used in simulations aimed at modelling moisture flux into the roof cavities. In the case study, the authors also give indoor climate data of residential dwellings in New Zealand.

This paper addresses the need for robust ceiling air permeability data in whole-house temperature and moisture transport simulations.

Eri is a short-stapled fibre that possesses an excellent soft feel and warmness to the wearer. Investigation of thermal comfort and moisture properties of Eri silk fabric provides the enhanced commercial scope for Eri silk-based clothing.

To examine the impact of process factors on thermal and moisture properties, three different single knit Eri silk structures were made, each with a different loop length and yarn count. Three different linear densities of Eri silk spun yarn (15, 20 and 25 tex) were selected. Three distinct knitted constructions, including plain jersey, popcorn and cellular blister, were created, along with two different loop lengths.

The novel cellular blister structure has shown appreciable thermal comfort properties than the other two structures. Yarn fineness and loop length were significant with most of the thermal comfort properties.

In recent times the Eri silk production is completely domesticated, so the new demand can easily be met by the producers. This research will create a new scope for Eri silk fibres in sportswear and leisure wear.

This study was conducted to explore the influence of knit structure, loop length and yarn count on the thermal comfort properties of the clothing.

The purpose of this paper is to investigate thermal comfort performances of socks produced from cotton and regenerated cellulosic fiber yarns by thermal resistance (by a newly designed foot thermal manikin), moisture management tester (MMT) parameters and permeability (air and water vapor) tests.

Single jersey fabrics and socks were knitted from 30 Ne yarns produced from cotton, different regenerated cellulosic fibers (viscose, modal, bamboo, micromodal, Tencel®, Tencel LF®) and their blends. Thermal resistances of the socks were compared by a newly developed thermal foot manikin in a more realistic way than measurements in fabric form. Besides air and water vapor permeability, moisture management parameters of the fabrics were tested to differentiate performances of cellulosic fibers.

Results show that air permeability, liquid absorption and transfer parameters measured by MMT are generally identical and better for regenerated cellulosic fabrics than cotton. Micromodal and Tencel® have better performances for liquid transfer and overall moisture management capacities are superior for bamboo and Tencel LF®. Thermal resistances of the socks are minimum for Tencel LF® having a cross-linked structure and maximum for viscose socks.

It is thought that thermal resistance measured in socks form is more realistic than fabric measurements and results of this study that can be valid for all knitted garments. Moreover, comprehensive material plan of the study is valuable for getting reliable results for regenerated cellulosic fibers that have small differences in cases of thermal resistance and liquid transfer.

In this paper, three research topics are presented referring to different aspects of multifield problems in civil engineering. The first example deals with long term behaviour of wood under multiaxial states of stress and the effect of moisture changes on the deformation behaviour of wood. The second example refers to the application of a three‐phase model for soils to the numerical simulation of dewatering of soils by means of compressed air. The soil is modelled as a three phase‐material, consisting of the deformable soil skeleton and the fluid phases – water and compressed air. The third example is concerned with computational durability mechanics of concrete structures. As a particular example of chemically corrosive mechanisms, the material degradation due to the dissolution of calcium and external loading is addressed.

This paper traces the evolution of objective measurement of textile hand and comfort from Pierce through modern methodology and approaches. Special emphasis is given to discuss the contribution of the Kawabata Evaluation System (KES) towards advancing the state of objective measurement. Laboratory case studies are used to show how data generated by the KES and other instruments can be integrated into a comprehensive approach that attempts to explain human comfort response to garment wear in terms of fabric mechanical, surface and heat and moisture transfer properties.