CAD Method to Design Complex Dobby Weaves with Large Repeats

The principle of a CAD method of converting the pre-designed figures in image form into complex dobby weaves with the appearances similar to the original figures is mainly introduced in this paper. A few designed weaves by the created CAD system are also given as examples of the practical application in the area of complex dobby weave designing.

Non-woven Industry Weaves a Beautiful Pattern

As one of the three backbone con- sumptions (apparel, home-textile, tech- textile or industrial applications), non- woven textile industry performed well in 2005, but problems still remain. An official from the State Development and Reform Commission - China’s top planner, mapped out economic blue- prints for this fast-growing sector in 2006.

纺织工程专业本科机织学课程“WEAVE”教学模式创新与实践

为了落实立德树人根本任务,以为国家和社会培养支撑纺织产业转型升级的复合人才为根本目标,结合课程特点、学情分析和教师角色,对纺织工程专业本科机织学课程进行了教学创新探索与实践。坚持以学生学习为中心,建设“WEAVE”教学模式。在“WEAVE”教学模式中,在教学内容、教学方法、教学评价体系方面,注重强调学生在学习中的主体地位,明确教师在学习过程中的辅助作用,引导学生高度参与课堂教学,加深学生对学习目标和学习成果的清晰认知,更好地培养学生的学习能力。“WEAVE”教学模式具有明显的纺织特色,在培养纺织行业人才方面具有一定的优势。

不同编织方式下陶瓷基复合材料表面流动特性数值计算研究

Ceramic matrix composites(CMCs) are one of the most promising materials in the field of gas turbines,with superior weight and thermal properties. Its surface morphology is different from the traditional casting airfoil components, which mainly comes from different weaving methods and different braided tow thickness. However, few people have studied the influence of surface morphology of ceramic matrix composites(CMCs) on the development of boundary layer and the resulting flow loss. In this paper, Tex Gen is used to generate different surface morphology structures of ceramic matrix composites(CMCs), and the surface flow characteristics of corresponding CMCs plates are numerically studied. It is found that the slope of the displacement thickness of the woven surface first increases and then decreases in the whole transition interval. Thicker braided tow thickness and denser braiding method will induce earlier flow transition phenomenon and produce greater flow loss;The flow loss on the surface of CMCs plate is mainly composed of the vortex loss in the pit and the boundary layer loss outside the pit, and the boundary layer loss is dominant. The weaving methods has a greater influence on the flow state and flow loss of the boundary layer.

Analysis on the turning point of dynamic in-plane compressive strength for a plain weave composite

Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.

Manufacture of Single Cotton Fabric with New Composition, Specified Bend from Yarn Gathered from Local Raw Material Cotton Fiber

The article created 21 types of fabrics for the new composition of dublerin. Tests of various types of weave, fiber composition and yarn count are shown in various ways. The physical and mechanical parameters of the test samples were determined and analyzed at the “Accredited Testing Laboratory for Light Industry Products” at the State Unitary Enterprise “Namangan Center for Testing and Certification”. The reason for such a low performance of the motos of number 15 produced in the scientific research work is that the linear densities of the body and the yarn are four times different, despite the weaving of the fabric. Elongation at break is also dependent on penetration.

Produced-water treatment: Application and research of combined fiber coalescence technique in offshore oilfield

When the process of extraction of oil from an offshore oilfield enters the advanced stages,the water content in the extracted fluid can be above 90%.The water quality is complex with many types of pollutants and highly emulsified water.Therefore,a key consideration in the production process of offshore oilfields is the efficient and economical treatment of the oil-containing produced water to make it suitable for discharge and recover oil pollutants.In this study,we developed a hydrophilic and hydrophobic combined fiber coalescence separator with composite fiber shapes using fiber induction and X/Uweaving.The separator is designed based on experimental observations of the mechanism of structure coalescence in the physical oil removal method.A pilot test was performed on an oil exploration platform in the Bohai Sea.At the designed flow rate,the separator reduced the total concentration of petroleum in the produced water from 2000 to 3000 mg/L to below 60 mg/L,with an average oil removal efficiency of 98.24%.Furthermore,it effectively reduced the number of organic compounds present in the water from 120 to 17 and removed 70% of the SS.The test results show that the proposed device can be used fr produced-water treatment on offshore platforms.

Coordinate-Parametric Matrix Model Inspired Square-Conjoint Pattern in Cross Woven for Conventional Bamboo Mat

In the study,it is proposed that a coordinate-parametric matrix model is performed to a square-conjoint pattern of cross woven(SCPCW)in the bamboo mat.The patterns of SCPCW are firstly detected according to the perspective of configuration,which is divided into the basic-monomer shape and the basic combination shape.Secondly,the compositions of design patterns in SCPCW are analyzed to attain the trend of curve shape.Based on the coordinate-parametric matrix model,the specimens of SCPCW are subsequently accomplished to elaborate the woven logic of bamboo mats.The digital innovation of SCPCW,defined by a mathematical resolution,is implemented by the software of Grasshopper(GH),which plays a crucial role in capturing image information by the Image Sampler component.Successively,the weaving logic of coordinated matrix is referred to apply in the computing component of Grasshopper software.Finally,the computer simulation could demonstrate that the coordinate-parametric matrix model of SCPCWwould be realized to analyze the micro-weaving structure and overall weaving effect in the bamboo mat.

Minimization of Air Consumption and Potential Savings of Textile Denim Fabric Manufacturing Process

One of the most important aspects of Bangladesh’s textile industry is denim. Bangladesh now has a new opportunity thanks to the global demand for denim among fashion industry professionals. Entrepreneurs from Bangladesh provide denim products to well-known international merchants all over the world. The worldwide denim market is predicted to expand by roughly 8% through the year 2020. We must raise the standard of denim if we are to keep up with the expanding industry. In contrast to projectile and rapier systems, air-jet weaving machines nowadays can weave practically all types of yarns without any issues and at higher rates. Due to this, air-jet looms are an excellent substitute for other weft insertion techniques. This kind of device still has one significant flaw, though, and that is the enormous power consumption brought on by the creation of compressed air. Researchers and manufacturers of air-jet looms have therefore worked very hard to find a solution to this issue and achieve a huge reduction in air consumption without compromising loom performance or fabric quality. Therefore, the purpose of this project is to look into ways to decrease air consumption and reduce auxiliary selvedge waste without any decrease in loom performance and fabric quality on existing air-jet weaving looms which reduce the manufacturing costs with process improvement. Just updating the air pressure allowed a weaving mill to reduce air usage by 11 cfm. So, with just almost no cost, a company with 100 looms could save $0.15 M each year, on compressed air. Two new methods for decreasing process costs on air jet looms have also been developed by this project work.

An Overview of 3D Thin Shell Textile Preforms

The automobiles, aircraft, and lightweight industries continuously demand thin near-net-shape preforms just out-of-machine as close to the final shape. This study addresses the possibilities of 3D thin shell textile preform as the solution of lightweight reinforcement in various applications. Investigation into the development of 3D thin shells has led to different manufacturing processes. However, 3D thin shell preforms are mostly made by weaving and knitting, but nonwoven, winding, and/or layup techniques have been reported for over a decade. Owing to the complex thin shell manufacturing processes, they are not similar to the conventional methods. The different 3D thin shell preforms can extend the opportunities for new applications in various technical fields. This study presents existing research gaps and a few potential issues to be solved regarding 3D thin shell preforms in the near future.

An Overview of 3D Thin Shell Textile Preforms

The automobiles, aircraft, and lightweight industries continuously demand thin near-net-shape preforms just out-of-machine as close to the final shape. This study addresses the possibilities of 3D thin shell textile preform as the solution of lightweight reinforcement in various applications. Investigation into the development of 3D thin shells has led to different manufacturing processes. However, 3D thin shell preforms are mostly made by weaving and knitting, but nonwoven, winding, and/or layup techniques have been reported for over a decade. Owing to the complex thin shell manufacturing processes, they are not similar to the conventional methods. The different 3D thin shell preforms can extend the opportunities for new applications in various technical fields. This study presents existing research gaps and a few potential issues to be solved regarding 3D thin shell preforms in the near future.

The Impact of Fabric Weave and Anisotropy on the Poisson’s Ratio in Technical Fabrics

Poisson’s ratio changes during the tensile stress of technical fabric samples due to the anisotropy of technical fabrics.This paper examines the effects of the type of weave and the anisotropic characteristics of the technical fabric on maximum tensile force,corresponding elongation,work-to-maximum force,elasticity modulus,and Poisson’s ratio when axial tensile forces are applied to samples cut at various angles in the direction of the weft yarns of the technical fabric.In the lab,3 cotton fabric samples of constant warp and weft density with different structural weave types(plain weave,twill weave,atlas weave)were subjected to the tensile force until they broke at the following angles:0°,15°,30°,45°,60°,75°,90°.Based on the different measured values of technical fabric stretching in the longitudinal direction and lateral narrowing,Poisson’s ratio is calculated.The Poisson’s ratio was calculated up to a relative elongation of the fabric of 8%,as the buckling of the fabric occurs according to this elongation value.According to the results presented in this paper,the type of weave of the fabric,the direction of tensile force,and the relative narrowing of the technical fabrics all play important roles in the Poisson’s ratio value.The Poisson’s ratio curve of a technical fabric under tensile stress(i.e.elongation)is primarily determined by its behaviour in the opposite direction of the elongation.The change in the value of the Poisson’s ratio is represented by a graph that first increases nonlinearly and then decreases after reaching its maximum value.

Plantation future of bamboo in China

In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which Chinas agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edible-shoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended.

Digital Jacquard Fabric Design in Colorful Mode

Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed at expanding past and present jacquard design and production methods towards innovative ends. In this paper, the design principles and design methods for unconventional digital Jacquard fabric design in colorful mode have been analyzed based on the new technologies and computer applied color theory. The results of this study will enhance further research in the area of digital textile.

Innovative Principle and Method for Digital Jacquard Fabric Designing

Digital jacquard fabric has its design concept and method directly borrowed from computer images and color modes, which enabled creation of jacquard fabric design that is far beyond what freehand patterns can express. In this paper, the principles of digital jacquard fabric design were classified into two parts, colorless mode and colorful mode, and an innovative layered combination design method has been suggested contenting with this new design concept, by which digital jacquard fabric can be designed from colorless single-layer structure to colorful compound structure. As a result, designed colorless and colorful jacquard fabrics are capable of expressing picturesque and photo-realistic effects with a mega level color number on face of fabric. It is envisaged that the results of the study are of tremendous benefit to the creation of new jacquard fabric with an inimitable digital effect and this creation pose no problem in mass production.

Principle and Method for Structural Design of Digital Woven Fabric

Digital woven textiles are one of the latest research areas of digital textiles. The key of research on design of digital woven fabrics lies in structural design. Nowadays, the application of digital design technology has fundamentally changed the concept of structural design of woven fabric, giving rise to design methods and effects that were deemed impossible before. A study has been carried out to analyze the nature of woven structures and the methods of structural design. This paper proposes an innovative principle and method of structural design under digital design concept, on which the design of digital gamut weaves and establishment of weave-database were presented to meet the requirement of balanced interlacement. It is envisaged that the results of this study will enhance future research in creation of digital woven fabrics, with particular emphasis on digital jacquard fabrics. Meanwhile, this study is also laid the foundation for the intelligent design of woven textile.

反导制导滤波技术研究

为了实现对下落段速度大、螺旋机动的弹道导弹的有效拦截,反导导弹必须有针对性的进行制导滤波技术的研究。文中创新性的采用拉普拉斯变换方法进行4态滤波设计,对目标加速度、加速度一阶导、加速度二阶导同时进行在线估计,滤波结果与3态滤波结果比具有延迟小、精度高的特点;同时结合已有Weave制导律,通过和3态滤波+比例导引、3态滤波+最优导引进行对比,得出4态滤波+Weave导引具有脱靶量小的优点。

STUDY ON THE MATHEMATICAL MODEL FOR FABRIC WEAVE DESIGN AND ITS APPLICATIONS

In the light of the mapping between[0,1]matrixes of fab-ric weaves,we establish in this paper a mathematical modelfor fabric weave design- One type of non- associative al-gebra composed of 7 basic transformations in a 2- elementfield.In view of practice,we expand the generative set ofmapping of this matematical model to cover the generaltransformation methods in traditional weave design.Takingthe algorethm of" Kronecker product" as an example,wefurthermore illustrate applied potentialities of the generativeset of mapping in the CAD of fabic weaves.

Influence of Weave Structures on the Tribological Properties of Hybrid Kevlar/PTFE Fabric Composites

The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive modification, and performing fiber surface modification. As fabric composites, the weave structures play an important role in the mechanical and tribological performances of the liners. However, hardly any literature is available on the friction and wear behavior of such composites with different weave structures. In this paper, three weave structures （plain, twill 1/3 and satin 8/5） of hybrid Kevlar/PTFE fabric composites are selected and pin-on-flat linear reciprocating wear studies are done on a CETR tester under different pressures and different frequencies. The relationship between the tensile strength and the wear performance are studied. The morphologies of the worn surfaces under the typical test conditions are analyzed by means of scanning electron microscopy （SEM）. The analysis results show that at 10 MPa, satin 8/5 performs the best in friction-reduction and antiwear performance, and plain is the worst. At 30 MPa, however, the antiwear performance is reversed and satin 8/5 does not even complete the 2 h wear test at 16 Hz. There is no clear evidence proving that the tensile strength has an influence on the wear performance. So the different tribological performance of the three weave structures of fabric composites may be attributed to the different PTFE proportions in the fabric surface and the different wear mechanisms. The fabric composites are divided into three regions： the lubrication region, the reinforced region and the bonding region. The major mechanisms are fatigue wear and the shear effects of the friction force in the lubrication region. In the reinforced region fiber-matrix de-bonding and fiber breakage are involved. The proposed research proposes a regional wear model and further indicates the wear process and the wear mechanism of fabric composites.

Improvement of Weld Quality Using a Weaving Beam in Laser Welding

This paper describes a way to improve the weld quality through suppressing the porosity formation and restraining the growth of columnar grains by using a weaving beam in laser welding. The experimental results show that the N2 porosity of beam-weaving laser welding low carbon steel can be remarkably reduced with increasing weaving frequency, and porosity can be eliminated when the weaving amplitude is only 0.5 mm; and the Ar porosity in the weld metal is decreased with increasing weaving frequency and amplitude when the welding speed is higher than 0.5 m/min. The beam-weaving laser welding of ultra-fine grained steel has been investigated. The experimental results show that beam-weaving laser welding with appropriate amplitude and frequency can partly restrain the growth of the columnar grain and improve the tensile strength of the weld metal.