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外文文献翻译完整版 译文3200多字 (含:英文原文及中文译文) 文献出处: Kar F, Fan J, Yu W. Comparison of different test methods for the measurement of fabric or garment moisture transfer propertiesJ. Measurement Science & Technology, 2007, 18(7):2033.英文原文 Comparison of different test methods for the measurement of fabric or garment moisture transfer propertiesF Kar, J Fan and W YuAbstractSeveral test methods exist for determining the water vapour permeability or resistance of textile fabrics or garments. The differences and interrelationships between these methods are not always clear, which presents a problem in comparing results from different test methods. This study is aimed at investigating the relationships between the test results from four typical test methods, including the moisture transmission test (Model CS-141), ASTM E96 cup method, sweating guarded hot plate method (ISO11092) and the sweating fabric manikin (Walter). For the range of air permeable knitted fabrics tested, it was found that good interrelationships exist between the results from the four types of test methods, although some discrepancies exist between different tests due to differences in testing conditions. Test results from different moisture transfer test methods can therefore be convertible with due consideration.Keywords: fabric, water vapour transmission rate, clothing comfort, water vapour resistance1. IntroductionMoisture transfer properties of textile fabrics and garments are important to the thermal comfort of clothed persons. A number of test methods have been developed to evaluate the moisture transfer properties of textile fabrics and garments. However, since the techniques and testing conditions of these tests are very different, results from these tests are not directly comparable. It is therefore necessary to investigate the differences and interrelationships between the results from these different test methods.Dolhan compared two Canadian Standards (CAN2-4.2-M77 and CAN/CGSB-4.2 No. 49-M91) and the ASTM E96 test methods for measuring the water vapour transmission properties and found that the results of these tests were not directly comparable because of the differences in the water vapour pressure gradients driving the moisture transmission in the different test methods Gibson 8 conducted an extensive investigation on the relationship of the test results from the sweating guarded hot plate (ISO11092) and those from the ASTM E96 Cup Method. In his work, permeable materials, hydrophobic and hydrophilic membrane laminates were tested and the results were standardized in the units of air resistance and water vapour transmission rate. It was found, except for the hydrophilic samples, there is a clear correlation between the results from the two tests. As the test condition in the guarded sweating hot plate tests resulted in much higher equilibrium water content in the hydrophilic polymer layer, which influences the polymers permeability, the water vapour transmission rate through the hydrophilic membrane is greater when tested using the sweating guarded hot plate. As pointed out by a number of previous researchers 7, 12, different relative humidity gradients present in the various test methods cause the intrinsic transport characteristics of hydrophilic polymers to change. For such fabrics, there tend to be poor correlations between different test methods that employ differing relative humidity gradients, since the resistance is a function of the water vapour concentration and temperature. Consequently, Lomax 11 pointed out the need for investigating the correlations of results from different test methods for different types of fabrics.Gretton et al 9 classified the fabric samples into four categories, including air permeable fabrics, microporous membrane laminated fabrics, hydrophilic membrane laminated/coated fabrics and hybrid coated/laminated fabrics, in investigating the correlation between the test results of the sweating guarded hotplate (ISO 11092) and the evaporative dish method (BS 7209). They showed that there is a good correlation between the two test methods for all fabrics except for the hydrophilic coated and laminated fabrics that transmit water vapour without following the Fickian law of diffusion.Recently, Indushekar et al 10 compared the water vapour transmission rates measured by a modulated differential scanning calorimeter and those by the conventional dish technique as specified in BS7209 for a wide range of woven based fabrics used in cold weather protective clothing. The study showed that results from these two test methods differ widely due to the differences in the water vapour gradients which occurred in the two methods.With the development of novel techniques for the measurement of moisture transmission properties of fabrics and garments, it is necessary to further investigate the relationship between different test methods. The present study was therefore aimed at investigating the correlations between the moisture vapour resistances/transmission rates measured using the newly developed sweating fabric manikin (Walter) 4, 6, the moisture transmission test (Model CS-141) 1, the ASTM E96 testing method 2 and the sweating guarded hot plate method 5. Since the correlations between the moisture vapour resistances/transmission rates tested using the different test methods are generally different for different categories of fabrics, the present investigation is focused on air permeable functional T-shirt type fabrics2. Methods2.1. SamplesFour interlock and four single jersey functional T-shirt fabrics were chosen from commercial sources for the experiment. The samples represent typical T-shirt fabrics in the market. The fabrics were sewn into long-sleeved T-shirts for the tests on the sweating fabric manikin (Walter) and the wearer trial experiments. Table 1 lists the characteristics of the fabrics used in this study.2.2 Experimental Measurement2.2.1 Moisture Transfer Test Method (Model CS-141)The instrument moisture transfer tester used in this test was developed by Ludlow. The company claims that this instrument can quickly and easily determine the water transfer rate of a fabric. This test is based on gas permeability law. This rule refers to the mass transfer ratio and the ability of the fabric to block moisture penetration, the pressure difference between the upper and lower sides of the fabric, and the thickness of the fabric. Figure 1 shows the structure of the moisture transfer tester. Small enclosed water tanks The clips on both sides sandwich the fabric sample in the middle of its vertical direction. Underneath the fabric is distilled water, which is less than half the height of the sink. Above is the air that has been dried with desiccant at the beginning of the test. The height of the air gap between the surface of the water in the tank and the lower surface of the material is 10 mm. The tank was placed in a chamber with a temperature of 20C and a relative humidity of 65%. During the experiment, moisture was transferred from the wet side (below the fabric) through the fabric sample to the dry side (above the fabric) and the humidity sensor maintained the monitoring of humidity changes in the upper part of the tank. During the time when the humidity increased from 50% to 60%, the rise in relative humidity was recorded every 3 minutes. The ratio of gas per hour per m 2 of steam in terms of g can be calculated by taking the data into the equation below.T = (269 107)(%RH 60/t)(H)/(100 0.02252) (1)Where: %RHaverage of the relative humidity difference between the upper and lower halves; tthe time interval between two successful data reads (t=3min); Hwater content per unit volume of the tank (H=45.74 gm-3).2.2.2. American Materials and Testing Association E96 vertical cup methodThis method is a very common method for testing the moisture transfer properties of fabrics. This method can be used to determine the rate of vapor-water transport in the vertical direction of the fabric under conditions of constant ambient humidity, constant humidity and a known fabric area. Figure 2 shows the principle of this test method. A cup filled with distilled water covered by fabric samples was placed in an adjustable environment with a temperature of 20C and a relative humidity of 65%. At the beginning of the experiment, 80 g of water was poured into the cup, which determined the distance from the lower surface of the fabric to the water surface to be 19 mm. The test lasted for five days, during which time the quality of each cup was recorded once a day. The vaporous water transfer rate (WVTR) per square meter per hour can be obtained by taking the data into the equation below.WVTR = G /tA (2)Where: Gthe value of the change in the weight of the cup covered by the fabric; tthe duration of the change in the mass of the cup, measured in h; Athe area of the fabric sample tested in m 2 .2.2.3. New thermal resistance wet resistance instrument test methodThe new thermal resistance wet resistance instrument was developed by Fan et al. This instrument complies with the test requirements specified in ISO (International Organization for Standardization) 11092. Compared with the conventional heat resistance and moisture resistance instrument, it makes it possible to simultaneously perform simulation tests on heat loss due to moisture evaporation and moisture evaporation loss. In addition, the instrument can be operated at subzero temperatures. Figure 3 shows the construction and working principle of the instrument.As can be seen from the measurement of evaporative heat loss, the total moisture resistance of the fabric sample placed on the porous board, sandwiched between the artificial skin and the air layer can be obtained by taking the data into the following formula.Ea sa ss et H ) H -PA (P = R (3) where: R et - total moisture resistance; A - area covered by the fabric sample (A = 0.0444 m 2); P ss - human skin temperature (controlled Water vapour pressure is saturated at 35C); P sa - Water vapor pressure is strong at ambient temperature; H a is relative humidity (%).In the experiment, five layers of fabric samples of the same variety were first laid on the instrument, and the value of Ret was read for the first time after stabilization. Then remove a layer of fabric. At this time, four layers of fabric remain on the instrument and read the Ret value. Push the class until all 5 layers of fabric are removed. Next, the obtained Ret value is plotted against the number of layers of the fabric when reading, and then adjusted using a linear regression principle to draw a line that approximates the original curve. The slope of this line is the moisture resistance of each fabric sample. size.2.2.4. Sweat Warmer Human Model (Walter) Test MethodWalter is the worlds first sweating warm mannequin developed by Fan and his colleagues. Figure 4 shows a sweating warm manikin wearing a T-shirt during the test. This test was conducted in a constant temperature and humidity laboratory at a room temperature of 20.05C, a relative humidity of 65.02%, and a wind speed of 0.50.3ms -1.Eight fabric samples were sewn into garments of the same size. During the test, the pants worn by the mannequin on the lower body remained consistent. The total moisture resistance can be calculated by the following equation after calculation.3. Results and analysisThe results of the four types of tests are listed in table. The moisture transmission rates measured by the moisture transmission test and the ASTM E96 cup method, expressed in units of gram per hour per square metre, are also converted to the moisture vapour resistance expressed in units so as to be comparable to the moisture vapour resistances measured by the sweating hot plate and the sweating fabric manikin.The result is a reduction of total moisture vapour resistance and thus an increase in moisture transmission rate. Since the moisture transmission test only lasts for 1 to 2 h, the effect of condensation is, on the other hand, not significant. For sample 8, the deviation from the trend line may be caused by the fact that it is relatively thick and therefore can absorb more moisture during the ASTM E96 cup method. The moisture absorption results in the swelling of cotton fibres and hence the reduction of the measured moisture transmission rate.4 ConclusionIn this study, four instruments were used to determine the vapor transmission rate or wet resistance of functional breathable t-shirt sports fabrics/clothing. From this study, it can be seen that for a typical functional T-shirt fabric, there are four kinds of test methods, namely “wet transfer test method (model CS-141)”, “ASTME96 vertical cup method”, and “new thermal resistance wet There is a close relationship between the resistance instrument test method and the Walter test method. The results obtained from any of the test methods in this study can be compared by using the correlation trend curve and the results obtained by another method. Some errors in the correlation curve can be explained by differences in the types of materials and testing conditions.中文译文织物或服装湿传递性能的不同测试方法比较作者:F Kar, J Fan and W Yu摘要现有几种测定织物 /服装汽态水渗透或湿阻的方法,这些方法相互之间的区 别与联系并没有得到明确提出, 这引出了一个新的命题, 即通过对比不同测定方 法的结果,找出它们之间的区别与联系。本课题致力于调查 4种典型测定方法, 包括“湿传递测试法(模型 CS-141) ” 、 “ ASTM (美国材料与试验协会,英文全称 American Society for Testing and Materials) E96正立水杯法” 、 “新式热阻湿阻仪器 测试法”和“出汗暖体人体模型(Walter )测试法” ,所得到的结果相互之间的 联系。实验结果表明,鉴于测试所用的针织物的透气性的差异范围,尽管这 4种方法的结果由于在不同的环境下进行测试而存在些许差异, 但它们仍然存在着 密切联系。因此,不同测试方法的结果经过适当调整可以相互转换。关键词:织物,汽态水传递比率,织物舒适性,湿阻1.引言纺织面料和服装的湿气转移性能对穿着者的热舒适性很重要。已经开发了许多测试方法来评估织物和服装的湿气转移性能。但是,由于这些测试的技术和测试条件差异很大,因此这些测试的结果不能直接比较。因此有必要研究这些不同测试方法的结果之间的差异和相互关系。Dolhan比较了两种加拿大标准(CAN2-4.2-M77和CAN / CGSB-4.2 No. 49-M91)和ASTM E96测量水蒸气传输特性的测试方法,并发现这些测试的结果不能直接比较,因为在不同的测试方法中水汽压力梯度的不同促使水分传输。吉布森8对出汗防护板(ISO11092)和ASTM E96杯法测试结果之间的关系进行了广泛研究。在他的工作中,测试了可渗透材料,疏水性和亲水性膜层压材料,并以空气阻力和水蒸气透过率为单位对结果进行了标准化。除亲水样品外,发现两种测试结果之间有明显的相关性。由于防护发汗热板试验中的测试条件导致亲水性聚合物层中高得多的平衡含水量,其影响聚合物的渗透性,所以当使用防汗热板进行测试时,通过亲水膜的水蒸气透过率更高。正如许多先前的研究人员指出的7,12,各种测试方法中存在的不同相对湿度梯度会导致亲水聚合物的固有传输特性发生变化。对于这样的织物,使用不同相对湿度的不同测试方法之间往往存在较差的相关性因为阻力是水蒸汽浓度和温度的函数。因此,Lomax 11指出需要研究不同类型织物的不同测试方法结果的相关性。Gretton等9将织物样品分为透气织物,微孔膜层合织物,亲水性膜层合织物和混合涂层/层合织物四类,研究了出汗防护板的测试结果(ISO 11092)和蒸发皿法(BS 7209)。他们表明,对于所有织物,两种测试方法之间存在良好的相关性,除了亲水涂层和层压织物在不遵循Fickian扩散定律的情况下传输水蒸气。最近,Indushekar等10比较了用调制差示扫描量热仪测量的水蒸汽透过率和BS7209中规定的用于寒冷天气防护服的各种织物基织物的传统洗碗机技术。研究表明,这两种测试方法的结果差异很大,这是由于两种方法中发生的水蒸气梯度不同。随着织物和服装湿气传输性能测量新技术的发展,有必要进一步研究不同测试方法之间的关系。因此,本研究的目的是研究使用新开发的出汗织物人体模型(Walter)4,6,湿度传输测试(CS-141型)1,湿度传感器ASTM E96测试方法2和防汗热板法5。由于使用不同测试方法测试的湿气阻力/透射率之间的相关性对于不同种类的织物通常是不同的,因此本研究集中在透气性功能T恤型织物2. 测试方法2.1测试样品此项实验的样品为 8块功能性 T 恤面料商品, 其中 4块的织物组织为双罗纹, 另外 4块为平纹。 这些样品代表了市场中典型的 T 恤面料。 在模拟试穿者试穿效 果的实验中,这些面料被缝制成了长袖 T 恤,穿在出汗暖体人体模型(Walter ) 身上。2.2 实验测量2.2.1 水分传递测试法(模型 CS-141)此项测试所用的仪器水分传递测试仪由 Ludlow 公司开发。该公司声称这台 仪器能够快速简便地测定织物水传递比率。 此项测试是基于 “气体渗透规律” 进 行的。 这条规律是指质量传递比率与面料阻隔水分渗透的能力、 面料上下两侧的 压强差以及该面料的厚度相关。 图 1展示了水分传递测试仪的结构。 小密闭水箱 两侧的夹子将面料样品夹在其垂直方向的正中间。 面料下方是高度低于水槽一半 的蒸馏水, 上方是在测试开始时经过干燥剂干燥过的空气。 水箱内水的表面至面 料下表面的空气间隙的高度为 10mm 。这个水箱被放置在一个温度为 20,相 对湿度为 65%的密室中。实验过程中,水汽从潮湿的一侧(面料下方)经面料样 品传递至干燥的一侧(面料上方) ,湿度传感器保持着对水箱上半部分湿度变化 的监测。 在湿度从 50%上升至 60%这个时间段内, 相对湿度的上升值每隔 3分钟 被记录一次。以 g 重计的每 h 每 m 2汽态水传递比率可通过将数据带入下列等式 中计算得到。T = (269 107)(%RH 60/t)(H)/(100 0.02252) (1)式中:%RH上半层与下半层之间的相对湿度差值的平均值; t 两次成功读 取数据的时间间隔(t=3min) ; H 水箱单位体积的水含量
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