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Article
Publication date: 1 May 1994

Xiaoming Tao

Presents a mathematical treatment of the large‐scale bending behaviour of multi‐ply yarn. Based on the assumptions that: each individual fibre in the yarn has the form of…

Abstract

Presents a mathematical treatment of the large‐scale bending behaviour of multi‐ply yarn. Based on the assumptions that: each individual fibre in the yarn has the form of a doubly‐wound helix; each fibre is an inextensible slender rod; and interaction between fibres is ignored. The yarn‐bending rigidity is calculated as an average rigidity of an assembly of coaxial helices. There is good agreement between the predicted and measured values of yarn bending rigidity for a wool worsted knitting yarn. Also predicts the position, curvature and twist components as well as the strain energy of the deformed fibre.

Details

International Journal of Clothing Science and Technology, vol. 6 no. 2/3
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 14 November 2008

George K. Stylios

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched…

Abstract

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 20 no. 6
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 12 April 2018

Rajendran Selvamani

The purpose of this paper is to study the analytical solutions of transversely isotropic thermo-piezoelectric interactions in a polygonal cross-sectional fiber immersed in…

Abstract

Purpose

The purpose of this paper is to study the analytical solutions of transversely isotropic thermo-piezoelectric interactions in a polygonal cross-sectional fiber immersed in fluid using the Fourier expansion collocation method.

Design/methodology/approach

A mathematical model is developed for the analytical study on a transversely isotropic thermo-piezoelectric polygonal cross-sectional fiber immersed in fluid using a linear form of three-dimensional piezothermoelasticity theories. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been analyzed numerically by using the Fourier expansion collocation method (FECM) at the irregular boundary surfaces of the polygonal cross-sectional fiber. The roots of the frequency equation are obtained by using the secant method, applicable for complex roots.

Findings

From the literature survey, it is evident that the analytical formulation of thermo-piezoelectric interactions in a polygonal cross-sectional fiber contact with fluid is not discussed by any researchers. Also, in this study, a polygonal cross-section is used instead of the traditional circular cross-sections. So, the analytical solutions of transversely isotropic thermo-piezoelectric interactions in a polygonal cross-sectional fiber immersed in fluid are studied using the FECM. The dispersion curves for non-dimensional frequency, phase velocity and attenuation coefficient are presented graphically for lead zirconate titanate (PZT-5A) material. The present analytical method obtained by the FECM is compared with the finite element method which shows a good agreement with present study.

Originality/value

This paper contributes the analytical model to find the solution of transversely isotropic thermo-piezoelectric interactions in a polygonal cross-sectional fiber immersed in fluid. The dispersion curves of the non-dimensional frequency, phase velocity and attenuation coefficient are more prominent in flexural modes. Also, the surrounding fluid on the various considered wave characteristics is more significant and dispersive in the hexagonal cross-sections. The aspect ratio (a/b) of polygonal cross-sections is critical to industry or other fields which require more flexibility in design of materials with arbitrary cross-sections.

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Article
Publication date: 14 June 2011

Zhaoli Wang, Yueqi Zhong and Shanyan Wang

The purpose of this paper is to show how shape analysis and quantitative characterization of fiber cross sections, with the aid of image analysis techniques, provide a…

Abstract

Purpose

The purpose of this paper is to show how shape analysis and quantitative characterization of fiber cross sections, with the aid of image analysis techniques, provide a quick, powerful approach to automated profiled fiber identification.

Design/methodology/approach

In this paper, an effective method of cross‐sectional shape characterization for profiled fiber identification is reported with extraction of the distance fluctuation curve of fiber cross‐sectional boundary to the centroid. By calculating their cross‐correlations using signal processing techniques, the authors tackle the problem of calibrating the starting points of fiber objects orientated arbitrarily in image successfully, which are difficult to deal with by means of image processing, to finish the normalization of distance fluctuation curves. For two fiber cross‐sections, the similarity degree of their boundary fluctuation curves normalized can effectively reflect the similarity degree of themselves.

Findings

Based on this, the method presented extracts the curves of all fiber cross‐sections in one sample, compares the similarity degrees between each other, and creates clusters to identify profiled fiber.

Originality/value

Experimental results validate that this curve can effectively characterize profiled fiber cross‐sectional contour for profiled fiber identification and the normalization method is feasible.

Details

International Journal of Clothing Science and Technology, vol. 23 no. 2/3
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 8 December 2020

Mohammad-Reza Saffari, Mehdi Kamali Dolatabadi, Abosaeed Rashidi and Mohammad Esmail Yazdanshenas

One of the recent applications of fabrics is to use them for sound insulation. Accordingly, due to their low production cost and low relative density, fabrics have drawn…

Abstract

Purpose

One of the recent applications of fabrics is to use them for sound insulation. Accordingly, due to their low production cost and low relative density, fabrics have drawn attention in some of the industries such as the automotive and aircraft industries. The present study is aimed to investigate the effects of the fiber cross-section, porosity, thickness of samples and fuzzing of the knitted fabric on the sound absorption coefficient.

Design/methodology/approach

In the present study, fabrics with three different stitch densities were knitted by yarns consist of three different forms of fiber cross-section shapes (circular, elliptical and plus-shaped). In this work, the sound absorption coefficient of knitted fabrics was investigated with regard to the different fiber cross-sections and structural parameters using an impedance tube.

Findings

As indicated by the obtained results, the cross-section, porosity, thickness and mass per unit area of the fabrics were the determinant factors for the sound absorption coefficient. In addition to, the sound absorption coefficient and porosity were shown to have an inverse relationship.

Originality/value

A section of the present paper has been allocated to the investigation of the effect of the fiber cross-section and fuzzing of fabric on the sound absorption of plain knitted fabrics.

Details

International Journal of Clothing Science and Technology, vol. 33 no. 4
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 18 April 2017

Adam C. Taylor, Stephen Beirne, Gursel Alici and Gordon G. Wallace

This paper aims to design and test a system capable of coaxial fused deposition modelling (FDM) and assess the coaxial fibres produced for their coaxial concentricity. The…

Abstract

Purpose

This paper aims to design and test a system capable of coaxial fused deposition modelling (FDM) and assess the coaxial fibres produced for their coaxial concentricity. The goal is to achieve concentricity values below the literature standard of 15 per cent.

Design/methodology/approach

This research discusses the design of the coaxial nozzle internal geometry and validates the modelling process by using computational fluid dynamics to assess its flow profile. Sequentially, this paper discusses the abilities of current additive manufacturing (AM) technology in the production of the coaxial nozzle.

Findings

The methodology followed has produced coaxial fibres with concentricity values as low as 2.89 per cent and also identifies a clear speed suitable for coaxial printing using polylactic acid (PLA) as the internal and external materials.

Research limitations/implications

The concentricity of the printed fibres is heavily influenced by the feed rate for the thermoplastic feedstock. This in turn alters the viscosity of the material to be printed, implying that a relationship exists between feed rate and print temperature, which can be further optimised to potentially obtain higher concentricity values.

Practical implications

This paper adds reliability and repeatability to the production of coaxially printed structures, the likes of which has numerous potential applications for biological printing.

Originality/value

The outcomes of this study will provide an AM platform to alter the paradigm of biofabrication by introducing a new level of versatility to the construction of biofabricated structures.

Details

Rapid Prototyping Journal, vol. 23 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 1 March 1991

M.F. Blackshaw, L.H. Lee and R. Burt

The trend towards high speed digital processing has stimulated the need for new substrate materials with superior electrical properties for multilayer printed wiring board…

Abstract

The trend towards high speed digital processing has stimulated the need for new substrate materials with superior electrical properties for multilayer printed wiring board (PWB) applications. Two important electrical substrate parameters are dielectric constant and dissipation factor. This study examines the effect of combining different resin and fibre systems for altering or possibly improving electrical performance. Resin systems studied include FR‐4, cyanate ester and polytetrafluoroethylene. Materials used for reinforcement include E‐glass, S‐glass and polytetrafluoroethylene based fibres. Results of the electrical and thermal characterisation work on the test vehicles built based on the mixed resin and fibre systems are reported.

Details

Circuit World, vol. 17 no. 4
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 18 May 2021

Baneswar Sarker and Shankar Chakraborty

Like all other natural fibers, the physical properties of cotton also vary owing to changes in the related genetic and environmental factors, which ultimately affect both…

Abstract

Purpose

Like all other natural fibers, the physical properties of cotton also vary owing to changes in the related genetic and environmental factors, which ultimately affect both the mechanics involved in yarn spinning and the quality of the yarn produced. However, information is lacking about the degree of influence that those properties impart on the spinnability of cotton fiber and the strength of the final yarn. This paper aims to discuss this issue.

Design/methodology/approach

This paper proposes the application of discriminant analysis as a multivariate regression tool to develop the causal relationships between six cotton fiber properties, i.e. fiber strength (FS), fiber fineness (FF), upper half mean length (UHML), uniformity index (UI), reflectance degree and yellowness and spinning consistency index (SCI) and yarn strength (YS) along with the determination of the respective contributive roles of those fiber properties on the considered dependent variables.

Findings

Based on the developed discriminant function, it can be revealed that FS, UI, FF and reflectance degree are responsible for higher YS. On the other hand, with increasing values of UHML and fiber yellowness, YS would tend to decrease. Similarly, SCI would increase with higher values of FS, UHML, UI and reflectance degree, and its value would decrease with increasing FF and yellowness.

Originality/value

The discriminant functions can effectively envisage the contributive role of each of the considered cotton fiber properties on SCI and YS. The discriminant analysis can also be adopted as an efficient tool for investigating the effects of various physical properties of other natural fibers on the corresponding yarn characteristics.

Details

Research Journal of Textile and Apparel, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1560-6074

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Article
Publication date: 2 January 2018

Dalia Calneryte, Rimantas Barauskas, Daiva Milasiene, Rytis Maskeliunas, Audrius Neciunas, Armantas Ostreika, Martynas Patasius and Andrius Krisciunas

The purpose of this paper is to investigate the influence of geometrical microstructure of items obtained by applying a three-dimensional (3D) printing technology on their…

Abstract

Purpose

The purpose of this paper is to investigate the influence of geometrical microstructure of items obtained by applying a three-dimensional (3D) printing technology on their mechanical strength.

Design/methodology/approach

Three-dimensional printed items (3DPI) are composite structures of complex internal constitution. The buildup of the finite element (FE) computational models of 3DPI is based on a multi-scale approach. At the micro-scale, the FE models of representative volume elements corresponding to different additive layer heights and different thicknesses of extruded fibers are investigated to obtain the equivalent non-linear nominal stress–strain curves. The obtained results are used for the creation of macro-scale FE models, which enable to simulate the overall structural response of 3D printed samples subjected to tensile and bending loads.

Findings

The validation of the models was performed by comparing the computed results against the experimental ones, where satisfactory agreement has been demonstrated within a marked range of thicknesses of additive layers. Certain inadequacies between computed against experimental results were observed in cases of thinnest and thickest additive layers. The principle explanation of the reasons of inadequacies takes into account the poorer quality of mutual adhesion in case of very thin extruded fibers and too-early solidification effect.

Originality/value

Flexural and tensile experiments are simulated by FE models that are created with consideration to microstructure of 3D printed samples.

Details

Rapid Prototyping Journal, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 30 September 2014

Denise Ferreira, Jesús Bairán, Antonio Marí and Rui Faria

A nonlinear finite element (FE) beam-column model for the analysis of reinforced concrete (RC) frames with due account of shear is presented in this paper. The model is an…

Abstract

Purpose

A nonlinear finite element (FE) beam-column model for the analysis of reinforced concrete (RC) frames with due account of shear is presented in this paper. The model is an expansion of the traditional flexural fibre beam formulations to cases where multiaxial behaviour exists, being an alternative to plane and solid FE models for the nonlinear analysis of entire frame structures. The paper aims to discuss these issues.

Design/methodology/approach

Shear is taken into account at different levels of the numerical model: at the material level RC is simulated through a smeared cracked approach with rotating cracks; at the fibre level, an iterative procedure guarantees equilibrium between concrete and transversal reinforcement, allowing to compute the biaxial stress-strain state of each fibre; at the section level, a uniform shear stress pattern is assumed in order to estimate the internal shear stress-strain distribution; and at the element level, the Timoshenko beam theory takes into account an average rotation due to shear.

Findings

The proposed model is validated through experimental tests available in the literature, as well as through an experimental campaign carried out by the authors. The results on the response of RC elements critical to shear include displacements, strains and crack patterns and show the capabilities of the model to efficiently deal with shear effects in beam elements.

Originality/value

A formulation for the nonlinear shear-bending interaction based on the fixed stress approach is implemented in a fibre beam model. Shear effects are accurately accounted during all the nonlinear path of the structure in a computationally efficient manner.

Details

Engineering Computations, vol. 31 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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