The four-roller compact spinning system is widely used today and is considered an improvement over traditional ring spinning because of its excellent yarn properties. Reducing energy consumption in compact spinning has always been a key issue for the textile industry. This paper proposed a method for installing an air guide on compact spinning to reduce energy consumption. Four types of air guides were designed with different side shapes (Type-N, Type-L, Type-R, and Type-LR), and the airflow characteristics in the converging zone were analyzed using numerical simulation. In addition, high-speed photography technology and image-processing technology were used to study the dynamic state of the fiber bundle in the flow field of the converging zone. The effectiveness of the preferred solution of the air guide was also verified by spinning experiments. The results revealed that the best air guide was Type-LR, achieving a 3.7% reduction in yarn hairiness even after a decrease in negative pressure by 800 Pa and a 58.4% reduction in power of the fan motor, surpassing the yarn quality observed without any air guide.
Objective In order to solve the problems of slow speed,low efficiency,and high cost in conventional manual quality inspection methods for sewing thread,this study proposes a machine vision-based method for sewing thread defect detection in seams.This study aims to achieve fast,accurate,and automated identification of common defects such as cast thread,jumper thread,and broken thread in seams.This study also highlights the importance and necessity of improving product quality and production efficiency in the textile and garment industry. Method This study adopts a two-step approach for defect detection.Firstly,a low-cost array camera was adopted to capture real-time images of the sewing seam and the DeblurGAN-v2 method was employed to remove motion blurriness from the images,aiming at improving image clarity.Secondly,the student-teacher feature pyramid matching method was applied for anomaly detection,which transfers the knowledge from a pre-trained ResNet-34 model as the teacher network to a student network with the same architecture,so as to learn the distribution of normal images.By comparing the differences between the feature pyramids generated by the two networks as a scoring method,the defect detection system made decisions on whether the image has anomalies,and marked the abnormal areas with a heat distribution map. Results The defects of flat stitch fabric and overstitch fabric were tested and the performance of the proposed method was evaluated in terms of recall and accuracy rates.The results show that the proposed method can effectively detect various sewing thread defects and has high recall and accuracy rates for different types of defects.This study also provided some examples of defect detection results and scores for different types of defects. Conclusion The feature pyramid matching technique is applied in the field of stitch trace detection.By adding the difficult sample mining technology,the average detection accuracy is increased to more than 95%,and the detection speed of a single image is less than 0.04 s.Aiming at image motion blur ring caused by jitter and fast movement.The DeblurGAN-v2 framework is used as the framework of deblurring algorithm,and the blueprint convolution is added to change the backbone network,and the processing speed of a single image is kept below 0.06 s.The model has excellent interference resistance and high processing speed,and can meet the requirement of stitch trace recognition.
Objective The detection of bobbin yarn margin is an important part of the automatic production process in the textile industry,of which the design of an image algorithm is a key part for facilitating the automatic bobbin change system.Because the bobbin installed on the take-up bar rotates in two directions and the front image of the bobbin is oval,it is necessary to design a bobbin yarn margin detection algorithm suitable for the actual production situation. Method In view of the special imaging effect of the bobbin and considering the actual production situation,the inverse projection transformation algorithm was designed based on the multi-point perspective model.The initial inverse projection transformation matrix was calculated according to the spatial position relationship between the bobbin and the camera,and then the bobbin area was segmented to obtain the inner and outer bobbin areas of the bobbin and calculate the position information of the inner and outer bobbin areas.The compensation matrix was set,and the transformation matrix was optimized according to the position information of the inner and outer bobbin and the element transformation characteristics of the transformation matrix.The polar coordinates of the image were expanded after the inverse projection transformation and the bobbin yarn margin was calculated according to the set yarn margin calculation criteria. Results The processing effect of this method and the experimental results were discussed in detail.The inverse projection transformation effect of the algorithm was compared with that of the conventional three-point perspective model.It was seen that the conventional inverse projection transformation was difficult to consider the transformation effect of the inner and outer cylinders,and the yarn width in the same direction of the yarn area was not equal or even different.Therefore,the compensation matrix was set based on conventional inverse projection transformation to optimize the effect of inverse projection transformation.The element value of the compensation matrix was determined according to the position relationship between the inner and outer barrels of the bobbin.Therefore,the inner and outer barrels of the bobbin were first segmented,and the contour of the inner and outer barrels was fitted.The position information of the inner and outer cylinder,such as roundness,direction angle and area size,were calculated by obtaining the contour of the inner and outer cylinder.The compensation matrix was solved according to the element transformation characteristics of the compensation matrix after obtaining the position information of the inner and outer drums and the yarn area width at the inner and outer drums.Taking the square calibration board as an example,the transformation characteristics of the compensation matrix elements were shown in compensation matrix factor transformation effect.The fifth bobbin was selected to calculate the compensation matrix,and the product of the initial transformation matrix and the compensation matrix were as the inverse projection transformation matrix.Considering the limitations of the transformation effect,the conventional ellipse polar coordinates were optimized,and the angle information of the ellipse was added to the polar coordinate transformation to obtain the polar coordinate expansion diagram of the corrected bobbin image.The yarn margin of the bobbin was obtained according to the specified yarn margin calculation criteria.The objective in this paper was to determine different types of yarn bobbins under the sampling angle,so that the two types of yarn bobbins could be considered separately in the experiment.The test results of partial yarn margin of cylindrical bobbin were shown in margin detection results.It was seen that the test error was mostly within 5 mm,but it reached over 10%under some circumstances.In fact,although the error of the bobbin with large margin is relatively large,it will not have a significant impact on the actual production.This is because the main purpose of this algorithm is to provide warnings when there is less yarn surplus.Therefore,as long as the yarn surplus is detected before it is used up,the system can calculate the remaining usage time based on the yarn usage speed.The test results of part of the yarn margin of the cone bobbin were shown in margin detection result.The test error was within 4 mm,the error accuracy was about 95%,and the yarn width of the sample with large error was within 40 mm. Conclusion In order to solve the problems of poor transformation effect and high requirement of experimental conditions in general inverse projection transformation algorithm,this paper proposes a yarn margin detection algorithm based on inverse projection transformation based on multi-point perspective model.The experimental results show that the algorithm proposed in this paper can obtain good transformation effect of inner and outer bobbin at the same time for different types of bobbins under the determined sampling angle,and the detection error of yarn margin is within 5 mm,which meets the practical production requirements.Compared with other inverse projection transformation algorithms,this algorithm is simpler to implement and has higher detection efficiency.In the future work,the bobbin at different angles and different distances,and design filters to further reduce the interference of external environmental factors on the algorithm will be further studied,to enhance the detection accuracy of the algorithm.
针对液体分散染料明显区别于粉状分散染料的应用性能和生态环保性,简述了液体分散染料发展历程和染料研磨技术要点,从染料应用性能方面评述了液体分散染料的质量控制因素及分析了已建立的液体分散染料稳定性快速评价指标的合理性,阐述了液体分散染料替代粉状分散染料的应用进展及连续热熔染色的新用途和需要解决的新问题.指出:液体分散染料应建立区别于粉状分散染料的稳定性和应用性能相协调的评价指标及质量标准;染色中选择较小的轧槽容积和均匀轧车以及增加轧前的喷淋装置都有利于染料对织物的渗透和织物着色均匀性;同时,研究集染色和功能性于一浴的功能液体分散染料,将是一种可从源头满足印染行业的重大节能减排技术需求.
为开发功能性含锌和含铜纤维及医用敷料在伤口护理中的应用,介绍了锌离子和铜离子的生物活性及其在伤口愈合过程中的作用,总结了国内外市场上各种含锌和含铜医用敷料及其制备方法,重点介绍了含锌和含铜的海藻酸盐纤维、壳聚糖纤维,以及通过静电纺丝、高分子材料复合加工、纳米技术等先进工艺制备的各种含锌和含铜医用敷料及其释放锌离子和铜离子的性能.指出锌离子和铜离子具有优良的抗菌及促进伤口愈合的功效,含锌和含铜医用敷料通过释放锌离子和铜离子,对创面常见的各种细菌有很强的抑菌作用,在烧伤、下肢溃疡、糖尿病足溃疡、褥疮等伤口护理中有重要的应用价值.
为响应国家实现双碳目标,对生丝检验阶段进行了初级活动数据采集,并采用生命周期评价(LCA)方法对传统检验和电子检测 2 种检验过程中的碳足迹进行核算.结果表明:生丝传统检验方法和电子检测方法的碳足迹分别为 0.2355 及 0.2336 kgCO2e/kg,温室气体(GHG)排放主要来自恒温恒湿间的用电;单个检验项目中切断检验的GHG排放最高,外观检验次之,二者的GHG排放分别占传统检测方法的 53.07％、36.88％;3 个委托检验项目中茸毛检验的GHG排放最高,为 0.0145 kgCO2e/kg,含胶率检验与单丝强伸度检验的排放均较低;不确定性分析表明每批丝的总质量对总排放的影响在 3.95％以内(95％置信区间).建立的生丝检验过程中初级活动数据的调研与分配方法,碳足迹核算以及不确定性分析的方法,可为丝绸行业进行碳足迹核算提供数据与方法参考.
为制备色彩饱和度高、不易褪色且制备过程环境友好的多彩纤维,研究人员开发了多种相关的技术,其中光子晶体形成的结构色纤维具有优良的特性.因此对近年来国内外关于光子晶体结构色纤维的研究进行了回顾,综述了组成结构色纤维的多维光子晶体的生色原理,重点总结了光子晶体结构色纤维的主要制备方法,包括传统纤维外部着色法、模板法组装和不同纺丝技术形成结构色纤维.大量的研究表明,光子晶体作为结构生色技术的基础材料,促进了光子晶体结构色纤维研究的蓬勃发展.此外,综述了多功能结构色纤维在穿戴、检测、传感等领域的研究和应用进展,分析了光子晶体纤维设计和应用的瓶颈问题,并对其未来发展趋势进行了展望.光子晶体纤维的机械性能、优异的色彩饱和度等光学性能和尺寸均匀性使其在可穿戴、传感、生物检测、环境响应等领域具有很好的应用前景.
Objective The sizes and morphologies of microbeads on beaded fibers will lead to great differences in the overall performance of electrospinning fiber membranes, and thus fiber membranes with specific functions can be prepared in a directional manner by adjusting the size and morphology of beads on beaded fibers. As an important factor affecting the electrospinning process, electric field has not been used as the main research object in the process of preparing beaded fibers up to date. Therefore, it is necessary to investigate the influence of applied voltage on the structure and morphology of microbeads during electrospinning.Method Beaded fibers were prepared by electrospinning using polystyrene（PS）. Light microscope and scanning electron microscope（SEM） were adopted to observe the morphology of fibers, and the influence of applied voltage on the morphology of microbeads was studied. By observing the beaded fibers intercepted in different areas of the electrospinning jet, the evolution of beading morphology during jet whipping was explored. At the same time, the finite element simulation software COMSOL was adopted to simulate the three-dimensional electric field, bead morphology and beaded fiber movement speed. The simulation results were compared with the experimental results for model validation.Results Based on the simulation results of the magnitude and direction of the electric field, it is evident that the strong electric field is mainly concentrated near the spinneret. As the spinning voltage increases, greater electric field strength in the spinning area leads to stronger tensile effect of the jet. This results in a beaded shape that is approximately circular at an applied voltage of 15 kV and the beaded fibers are bent disorderedly. When the applied voltage is 25 kV, the shape of the beads is close to the spindle shape, and the fibers between the beads are more regular and orderly. As the spinning voltage increases, the speed of the beaded fibers gradually increases. When the voltage is in the range of 20 and 25 kV, the speed of the beaded fibers increases more significantly, because at larger spinning voltages, the solution in the jet is more polarized, the charge on the jet surface is higher, and the force of the electric field is stronger. Owing to the larger surface area of the bead, more charge is generated by the electric field polarization of the jet in the beaded part, which is associated to stronger the electric field drafting, resulting in a greater speed in the beaded part than the speed of the fiber part. It is clearly shown that only the Shish-Kebab（string crystal） structure exists in the linear segment of the jet. This is because the strong electric field is concentrated near the spinneret and the polymer is strongly sheared or stretched. Gradual formation of a beaded structure is observed at the end of the straight segment, because the large tensile force of the electric field causes the jet to break, the broken jet is directly drawn from the Taylor cone, and the droplet tends to contract to form beaded fibers. The result also shows that the closer is the fiber morphology intercepted in the spinning direction to the collector, the longer the electric field of the jet is subjected to and the longer the whipping disturbance action time. The shape of the beads gradually tends to spindle shape under the action of stretching. Conclusion In this paper, PS was used as raw material to prepare beaded fiber membranes by electrospinning method, and the evolution process of solution electro spun PS beaded fibers and the influence of spinning voltage on beaded morphology and fiber speed were investigated. The experimental results provide a theoretical basis for the controllable preparation of beaded fibers. 1) In the process of electrospinning, as the applied voltage increases, the stretching effect of the jet is more obvious, the beaded shape gradually changes from an approximate sphere to a spindle shape, and the movement speed of the beaded fiber also increases with the increase of the applied voltage. 2) The beaded structure is not formed on the linear segment of the jet, and gradually forms in the whipping zone, and the jet zone is made closer to the collector, the jet is subjected to the electric field and whipping action for a longer time, and the stretching effect of the beaded fiber is more obvious.
Objective Aiming at uneven of segment colored yarns made by three-roller and four-roller methods, coaxial double rear rollers were adopted to achieve the same linear density cotton/wool siro segment colored yarn by the method of two sets of roving at the same spindle position and equal coupled feeding. Two rovings are fed on the same position, and the drafting control condition of two rovings is consistent. The roller speed can be coupled to achieve equal fiber feeding. However, the spinning process, yarn structure and properties of cotton/wool siro segment colored yarn produced by coaxial roller spinning technology are rarely studied. Method Cotton/wool siro segment colored yarn with constant linear density was spun on HFX-A4J ring spinning frame. Two rovings were fed into the coaxial double rear roller equally at the same position. The lengths of spinning segmentation time were 1, 2, 4, 8 s, and the mass ratio cotton to wool during spinning were 87.5/12.5, 80/20, 75/25, 62.5/37.5 and 55/45. The influences of the proportion of mass ratio cotton to wool and the segmentation time on the breaking strength, evenness and hairiness of the colored yarn were investigated. The longitudinal and sectional yarn morphologies were observed with the KH1300 three-dimensional video microscope made by Questar Ltd.Results As is shown in the longitudinal and cross-sectional images of the yarn, the segment color effect of the yarn is more obvious with the increase of the difference in the mass ratio cotton to wool and the segmentation time. Owing to the different mass ratio cotton to wool in the adjacent two segments, the segment color effect appears in the longitudinal direction of the yarn. With the longitudinal observation results of the yarn, the longer the segmentation time is, the longer is the color segment length. Cross-sectional observations show that the cotton and wool fibers are compressed and wrapped in the yarn to form a structure similar to Yin and Yang fish of the Tai Chi pattern. When the mass ratio cotton to wool is constant, the breaking strength of the yarn decreases as the split time increases, and when the segmentation time is fixed, the yarn breaking strength decreases with the increase of the segment mass ratio cotton to wool difference. When the segment time is shorter than 2 s, the yarn breaking strength decreases slightly with the increase of segment mass ratio cotton to wool difference. When the segmentation time is more than 4 s, the breaking strength of yarn decreases greatly with the increase of segment mass ratio cotton to wool difference. The evenness of cotton/wool segment colored yarn suggested that when the mass ratio cotton to wool is constant, the evenness increases with the increase of segmentation time. When the segment ation time is fixed, the unevenness of the yarn increases with the increase of segment mass ratio cotton to wool difference. With the increase of segment time, the ratio of roller speed change transition time to segmentation time decreases, the difference between real mass ratio cotton to wool and the designed value decreases, and the CV value of yarn increases with the increase of segment mass ratio cotton to wool difference.Conclusion As the diameter of wool fiber is thicker than cotton fiber, the total number of fibers in the cross section of yarn segment decreases with the increase of the mass ratio of wool, which reduces the breaking strength of the yarn segment and ultimately the breaking strength of the whole yarn. When the segmentation time is within 2 s and the difference of mass ratio cotton to wool is not more than 75/25, the cotton/wool segment colored yarn with weak segment color effect is produced, and the breaking strength and evenness of the yarn meet with the requirements of wearing performance. With such a yarn, woven fabric can be designed for colored patterns. This spinning method enriches the product types of existing fancy yarns. Meanwhile, under the condition of simple modification of the spinning frame, the strand-style wool-like segment color yarn is produced.
Objective The application of natural dyes in textile printing and dyeing has attracted extensive attention because of their non-toxic and harmless characteristics. In order to improve the color yield and color fastness of plant dye dyeing products, mordant dyeing treatment is often needed in the dyeing process, but this will lead to long dyeing process and a large number of metal ions in wastewater. Metal ions were introduced into natural dye molecules in advance through complexation reaction to prepare metal complexed plant dyes, and their dyeing properties and influencing factors on textiles were studied in detail. These studies were deemed necessary for developing short dyeing process with natural dyes and achieving energy saving and emission reduction.Method In this paper, catechin-iron ion complex dye C-Fe was prepared by hydrothermal method through the coordination reaction between catechin and metal ion Fe 2+ . Fourier transform infrared spectroscopy（FT-IR）, ultraviolet visible spectrophotometer（UV-VIS）, scanning electron microscope energy spectrometer（EDS） and X-ray photoelectron spectroscopy（XPS） were adopted to characterize and analyze the structure of the complex dyes. The dyeing of a silk fabric with iron ion complexed catechin was studied by grinding dispersion method. The influences of technological parameters such as pH value, dyeing temperature and dye dosage on the K/S value of textiles were analyzed, and the technological conditions were optimized.Results Energy spectrum analysis of plant complex dyes showed that the C-Fe molecules contained not only C and O elements, but also Fe elements（Fig.2, Tab.1）. Based on the energy spectrum scanning component element content analysis and the structure analysis of the complex dye, the complex ratio of C-Fe molecule was calculated as 1：2. UV-VIS spectrum analysis showed that the maximum absorption wavelength of catechin was red shifted after complexation with metal ions, which was consistent with the law that the UV-VIS spectrum of dye molecules moved to the long wavelength direction caused by the attraction of metal ions to electrons（Fig.3）. IR spectrum analysis showed that the complex dye C-Fe produced a new absorption peak at 556 cm -1 , indicating that it was the stretching vibration peak of Fe—O bond formed after coordination（Fig.4）. X-ray photoelectron analysis showed that the peak position of Fe element was found at 706.7 eV for the complex dye C-Fe（Fig.5）. The coordination of metal ions had different effects on the whole molecular chemical environment. The complex dye occurred on the adjacent hydroxyl groups or the adjacent hydroxyl groups and carbonyl groups of the benzene ring（Fig.6, Fig.7, Tab.2 and Tab.3）.A complex dye suspension with an average particle size of 405.47 nm was obtained by grinding and dispersion（Fig.8）. The test showed that the optimal process parameters for dyeing silk fabrics with complex dye C-Fe were pH value of 4, dyeing temperature of 90 ℃, and temperature maintaining and continuous dyeing for 60 min（Fig.9, Fig.10 and Fig.11）. The color fastness to sunlight and rubbing of silk fabrics dyed with complex dye C-Fe reached grade 3, and the color fastness to perspiration and soaping were all above grade 4（Tab.4）. The UPF value of silk fabrics dyed with complex dye was 72, reflecting excellent ultraviolet protection performance（Tab.5）.Conclusion In this paper, plant complex dyes were prepared by the coordination reaction between plant dyes and metal ions, and then the silk fabric was dyed with good dyeing effect, and the fabric demonstrated good color fastness and UV resistance. The experimental results show that the preparation of plant complex dyes from plant dyes as raw materials is feasible for textile dyeing. It is expected to be developed as a short process technology for plant dye dyeing, which provides a theoretical basis for the development of metal complex natural dyes and their application in textile dyeing.
针对传统针织护膝热湿性能不佳、结构分区不够明确等问题,结合人体工学分析了人体腿部的形态特征和热湿分布特征,在满足腿部曲面的基础上建立了匹配腿部热湿需求的纬编成形护膝分区.选用 75 dtex(288 f)×2、150 dtex(96 f)涤纶DTY和 1 120 dtex橡筋纱制备了 14 种不同组织结构的样品,并对样品进行透气性及液态水分管理测试.根据针数和横纵密的关系对护膝结构进行设计,并通过高、中、低热湿区域对护膝进行热湿功能分区.对纬编成形护膝与市售针织护膝进行热成像和温湿度对比测试.结果表明:不同组织结构的样品热湿性能存在一定差距;与单一结构且分区模糊的针织护膝相比,热湿分区设计的护膝具有较好的热湿舒适性,可增加穿戴者在运动中的舒适性及运动表现.
模块化服装以其可拆卸可重组的特性成为服装向可持续设计绿色低碳转型的重要形式,针对目前对于模块化服装的研究主要集中于设计方法的探索,缺乏有关影响用户对模块化服装使用与态度因素的研究.基于技术接受度模型,引入服装功能性作为外部变量,构建模块化服装用户使用意愿模型并提出 7 个假设,使用问卷星软件对 141 名 18～26 岁的青年进行问卷调查,通过SPSS软件检验数据的信度与效度,经信度与效度检验合格后,通过AMOS软件结合结构方程模型对数据进行模型适配度分析及假设检验.研究结果表明:模块化服装的功能性对感知有用性和感知易用性均有显著正向影响且影响较大(P<0.001);感知有用性对使用态度具有显著正向影响(P<0.001);模块化服装的感知易用性对感知有用性具有显著正向影响(P<0.001);模块化服装的使用态度对行为意向具有显著正向影响(P<0.001),提高模块化服装的功能性、感知有用性及感知易用性可增加用户对模块化服装的使用意愿;模块化服装在设计时可将风格倾向休闲运动方向,并重点考虑颜色搭配.
针对柔性应变传感器目前存在的灵敏度低、应变范围窄、反复拉伸后性能不稳定、功能单一等问题,采用预拉伸浸渍法以商用弹性包芯纱为柔性基体、水性聚氨酯(WPU)为分散剂和黏合剂、长银纳米线(AgNWs)为导电材料制备了具有应变传感与电热双功能的包芯纱.借助X射线衍射仪、扫描电子显微镜、数字万用表、万能试验机、菲力尔热像仪对AgNWs的晶体结构及双功能包芯纱的形貌结构、电学性能、力学性能、电热性能进行表征和分析.结果表明:当弹性包芯纱的预拉伸应变量为 30%且AgNWs的负载量为 15%时,制备的双功能包芯纱的鞘层棉纤维上形成了致密的AgNWs导电网络;在宽应变范围(0%～70%)内呈现明显的应变传感性能,灵敏度最高可达12.8,反复拉伸后的应变传感和力学性能稳定;在手指的运动监测中,手指发生小幅度和大幅度的弯曲变化,双功能包芯纱均能做出相应的电信号响应,体现了高灵敏度;5 V电压下,静态拉伸范围为 0%～50%时,双功能包芯纱的温度变化范围为 49.8～65.7℃,体现了优异的电热性能.
针对人体衣物属性识别存在衣物分割困难、颜色易扭曲、识别效率和准确率低的问题,提出一种基于ClothResNet模型的高效人体衣物颜色识别方法,模型以ResNet18 网络为基础,设计优化的金字塔池化模块以捕获图像中的多层语义信息,融合坐标注意力机制以关注人体衣物轮廓信息,融入空洞卷积以提升网络效率,从而利用多重信息提高人体衣物识别精确率.针对人体衣物属性数据集不足的问题,利用公开数据集活动模板(回归ATR)原始彩色图像构建衣物属性数据集pcaparsing.性能对比实验表明,ClothResNet模型在衣物颜色属性识别中的平均精确率达到 94.49%,结果均优于同类方法.该识别方法在中小规模的人体衣物颜色识别系统具有广泛且重要的应用前景.
为提高半导体制冷服的制冷效率和穿着热舒适度,梳理了近年来国内外相关研究成果,将半导体制冷服的制冷系统分为冷源模块(包括制冷部分和热端散热部分)和冷端传热模块进行讨论.针对冷源模块,提高冷源制冷效率的方法有改善电源输入和提高热端散热性能.热端散热方式有强制风冷、液冷和热管散热,可通过改变不同散热方式下的各种参数来提高热端散热性能.针对冷端传热模块,传热方式有液冷传热、风冷传热和接触传热,可根据不同工况选择合适的传热方式.与传热部分的结构、介质相关的各项参数是影响传热效率和穿着者热舒适度的重要因素.热舒适度实验是评价和优化制冷服的重要方式,实验时需考虑装置、环境、人体等各项因素,建立人体-制冷服-环境的热舒适度模型是一种高效的分析和处理方法.综合各方面研究总结出影响半导体制冷服制冷效率和穿着热舒适度的因素,可为半导体制冷服各部分选型、设计优化和实验评估提供思路.最后提出:轻量便携、智能可控、高舒适性、适用于多场景的半导体制冷服以及利用半导体双制特性研发的空调服将成为未来的研究方向.
为预测染色过程中初始阶段染液侵入织物的流体流动和化学反应过程,以棉织物染色过程为例,建立了包含界面效应的纤维密度函数和哈根-泊肃叶方程,构建了织物润湿阶段的染色动力学和传质模型,模拟了染液侵入织物的染色过程,并通过实验进行了模型验证.结果表明:染液在织物中的流动主要是表面张力的作用,在重力的影响下,染液在织物中的流速随着上升高度逐渐减小,表面张力增大,织物内染液流速也会随之增大;纤维体积分数的增大会导致织物的毛细流动更快地达到平衡状态,从而使染液的扩散时间变短,织物染液浓度降低;染液与纤维之间接触角的变化会影响纤维的润湿性,接触角越大,织物的疏水性越好,染液越难以附着在织物表面,导致织物内染液浓度降低;流体的黏度越大,织物内染液流速越小,染液扩散速率越低.
为改善常规压力袜因压力过高而易给人体带来穿脱困难的问题,采用玻璃化转变温度接近人体体表温度的形状记忆氨纶(SMPU)与锦纶编织并设计 3 种平纹衬垫组织衬垫比的形状记忆氨纶压力袜.分别对SMPU的玻璃化转变温度和形状记忆性能,以及形状记忆氨纶/锦纶(SMPU/PA)包覆纱的形状记忆性能、拉伸强力、弹性回复性能进行评价.探究形状记忆氨纶压力袜袜筒部位平纹衬垫组织的衬垫比以及衬垫纱的送纱张力对人体脚踝最细处压力的影响.结果表明:人体体表温度即可触发SMPU的形状记忆性能,SMPU和SMPU/PA 包覆纱均具有良好的形状记忆性能;SMPU/PA包覆纱在玻璃化转变温度以上时的弹性回复率和断裂强力比玻璃化转变温度以下时分别提高 24.76%、降低 18.56%;以SMPU/PA包覆纱为衬垫纱制得的SMPU压力袜,其袜筒部位的压力在温度达到玻璃化转变温度以上与玻璃化转变温度以下时相比最大可提高 16.26%;且衬垫比为 1∶3,送纱张力为 8cN时,SMPU压力袜的压力最大可达到 2 841 Pa.
为探究氧化铝纤维在满足纺纱条件下其拉伸断裂强度在实际应用时的特性,选用不同线密度的单股氧化铝纱线并分别进行合股和加捻,测量不同合股数及捻度下氧化铝纱线的拉伸断裂强度,综合分析合股数和捻度对氧化铝纱线拉伸力学性能的影响规律,确定氧化铝纱线合股加捻的最佳工艺参数.结果表明:纱线合股后氧化铝纱线拉伸性能发生明显下降,且断裂强度与合股数呈反比,当采用 5 根单纱合股时,断裂强度相比于单根氧化铝纱线下降了 9.9%;对合股后的氧化铝纱线进行加捻后,随着捻度的增加,氧化铝纱线断裂强度均呈现先增加后减小的趋势,临界捻系数在 60～80 之间.
为探讨数字孪生在纺纱领域应用前景及价值,进一步促进纺纱领域的高质量发展,首先围绕提升纱线质量分析了纺纱领域的实际特点,并提出了数字孪生在纺纱领域的应用前景;然后分析了纺纱高质量发展中影响成纱质量的因素,以及相关因素的抽象模型与数字孪生抽象模型间的映射关系,并且在此基础上分析了数字孪生在纺纱领域不同情况下的核心理论,着重分析了非理想状态下的数字孪生优化方案;其次根据纺纱领域的特点提出了数字孪生在纺纱领域具体应用的解决方案及其应用的实际价值;最后提出:数字孪生在纺纱领域的应用要重点结合纺纱领域的特点,实现数据模型与机制模型的深度整合.
针对钢领内表面圆度在人工接触式测量中存在主观干扰及自动化程度低等问题,提出一种基于线结构光的钢领内表面圆度测量方法.通过构建图像掩模提取钢领内表面线结构光条纹的感兴趣区域,采用基于主成分分析的改进Steger方法,通过计算条纹法线方向的二阶泰勒展开得到亚像素级条纹中心,提升算法效率.由线结构光条中心坐标相机内外参数、光平面方程及旋转轴方程重构钢领内表面三维点云数据,根据圆度评价方法建立基于点云数据的钢领内表面圆度的测量模型.实验结果表明,本文方法所测最大偏差为 5.8 μm,与文献中投影法所测结果相比更加精确,重复性测量标准差为 0.725,且算法运行时间小于40 ms.
