1、Designation: D 1518 85 (Reapproved 2003)Standard Test Method forThermal Transmittance of Textile Materials1This standard is issued under the fixed designation D 1518; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the overallthermal transmission coefficients due to the combined action ofco
3、nduction, convection, and radiation for dry specimens oftextile fabrics, battings, and other materials within the limitsspecified in 1.2. It measures the time rate of heat transfer froma warm, dry, constant-temperature, horizontal flat-plate upthrough a layer of the test material to a relatively cal
4、m, coolatmosphere.1.2 For practical purposes, this test method is limited todeterminations on specimens of fabrics, layered fabric assem-blies, and battings having thermal transmittances (U2,asdefined in 3.1.2) within a range of 0.7 to 14 W/m2K andthicknesses not in excess of 50 mm.1.3 The coefficie
5、nts obtained apply strictly only to theparticular specimens tested and for the specified thermal andenvironmental conditions of each test. This test method givesvalues that are valid for comparison under the same conditionsof test, that is, with the specified air velocity, temperaturedifference betw
6、een the warm plate and the cool air, and air gapfor measuring cool air temperature.1.4 The values stated in metric units are to be regarded asthe standard. Conversion factors, for thermal conductance andconductivity and thermal resistance and resistivity, to otherunits in common use are given in Tab
7、les 1-51.5 This standard does not purport to address the safetyconcerns associated with its use. It is the responsibility ofwhoever uses this standard to consult and establish appropri-ate safety and health practices and determine the applicabilityof regulatory limitations prior to use.2. Referenced
8、 Documents2.1 ASTM Standards:D 123 Terminology Relating to Textiles2D 1777 Method for Measuring Thickness of Textile Mate-rials23. Terminology3.1 Definitions:3.1.1 bulk density, napparent mass per unit volume.3.1.1.1 DiscussionIn testing the thermal transmittance offabrics, bulk density is calculate
9、d from the fabric weight perunit area and the thickness value used to calculate thermalconductivity.3.1.2 clo, nunit of thermal resistance defined as theinsulation required to keep a resting man (producing heat at therate of 58 W/m2) comfortable in an environment at 21C, airmovement 0.1 m/s, or roug
10、hly the insulation value of typicalindoor clothing.3,4(Syn. intrinsic clo).3.1.2.1 DiscussionNumerically the clo is equal to 0.155Km2/W.3.1.3 heat transfer coeffcient, nsee thermal transmit-tance.3.1.4 intrinsic clo, nsee clo.3.1.5 specific clo, nthe specific thermal resistance in clounits per unit
11、thickness.3.1.6 thermal conductance, nsee thermal transmittance.3.1.7 thermal conductivity, ntime rate of unidirectionalheat transfer per unit area, in the steady-state, between parallelplanes separated by unit distance, per unit difference oftemperature of the planes.3.1.7.1 DiscussionNumerically,
12、thermal conductivityequals the product of the heat transfer coefficient and thedistance separating the planes. Thus, k, the thermal conductiv-ity of the fabric only, is the product of U2and the fabricthickness. Units of thermal conductivity are W/mK.3.1.8 thermal resistance, nreciprocal of thermal t
13、ransmit-tance.3.1.9 thermal resistivity, nreciprocal of thermal conduc-tivity.3.1.10 thermal transmittance, ntime rate of unidirectionalheat transfer per unit area, in the steady-state, between parallelplanes, per unit difference of temperature of the planes (Syn.thermal conductance, heat transfer c
14、oefficient).1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.51 on Chemical Conditioningand Performance.Current edition approved July 26, 1985. Published September 1985. Originallypublished as D 1518 57 T. Last previous
15、 edition D 1518 77.2Annual Book of ASTM Standards, Vol 07.01.3American Society of Heating, Refrigerating, and Air-Conditioning Engineers.4Gagge, A. P., Burton, A. C., Bazett, H. C., Science, Vol 94, Nov. 7, 1941, pp.428430.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Consh
16、ohocken, PA 19428-2959, United States.3.1.10.1 DiscussionThermal transmittance is expressed aswatts per square metre of test specimen per kelvin differencebetween the hot plate and the cool atmosphere (W/m2K).Thermal transmittance for three different cases is deter-mined in this method:U1= combined
17、thermal transmittance of the test specimenand air.Ubp= thermal transmittance of the plate without fabriccover (“bare plate”). This property reflects the in-strument constant and is used to standardize theplate, and, in conjunction with U1, is used in thecalculation of U2.U2= thermal transmittance of
18、 fabric only. This valuecorresponds to the C value (W/m2K) defined andused by ASTM and ASHRAE.4In the calculation ofthis value the assumption is made that the boundarylayers of the bare plate and the boundary layers ofthe fabric are equal. Experimental results indicatethat the U2values are valid whe
19、n tested within thelimits specified in Section 1.3.1.11 total clo, nthe intrinsic clo plus the thermal resis-tance from the air boundary.3.1.12 For definitions of other textile terms used in thismethod, refer to Terminology D 123.3.2 Definitions of Terms Specific to This Standard:3.2.1 effective ins
20、ulation ratio, nindicates the increase ininsulation afforded by the fabric in comparison to the uncov-ered test plate under specified conditions of test.3.2.2 mean temperature, nthe average of the hot platetemperature and the temperature of the calm, cool air thatprevailed during the test.4. Signifi
21、cance and Use4.1 The thermal transmittance of a fabric or batting is ofconsiderable importance in determining its suitability for use infabricating cold weather protective gear and clothing. Thethermal interchange between man and his environment is,however, an extremely complicated subject which inv
22、olvesmany factors in addition to the equilibrium insulation values offabrics and battings. Therefore, measured thermal transmit-tance coefficients can only indicate relative merit of a particularmaterial.4.2 The measurement of heat transfer coefficients is a verydifficult and highly technical field,
23、 and it is not practical in aTABLE 1 Conversion Factors for Thermal ConductivityATo ConvertThermal Con-ductivityMultiply byFromtoW/mKBWcm/m2K W/cmK cal/scmK kg-cal/hmKkg-calcm/hm2KBtu/hftFBtuin/hft2Fin/clo mm/cloW/mK 1. 1. 3 10+21. 3 1022.388 3 1038.598 3 1018.598 3 10+15.778 3 1016.934 6.093 1.548
24、3 10+2Wcm/m2K1. 3 1021. 1. 3 1042.388 3 1058.598 3 1038.598 3 1015.778 3 1036.934 3 1026.093 3 1021.548W/cmK 1. 3 10+21. 3 10+41. 2.388 3 1018.598 3 10+18.598 3 10+35.778 3 10+16.934 3 10+26.093 3 10+21.548 3 10+4cal/scmK 4.187 3 10+24.187 3 10+44.187 1. 3.6 3 10+23.6 3 10+42.419 3 10+22.903 3 10+32
25、.551 3 10+36.480 3 10+4kg-cal/hmK 1.163 1.163 3 10+21.163 3 1022.778 3 1031. 1. 3 10+26.720 3 1018.064 7.087 1.8 3 10+2kg-calcm/hm2K 1.163 3 1021.163 1.163 3 1042.778 3 1051. 3 1021. 6.720 3 1038.064 3 1027.087 3 1021.8Btu/hftF 1.731 1.731 3 10+21.731 3 1024.134 3 1031.488 1.488 3 10+21. 1.2 3 10+11
26、.055 3 10+12.679 3 10+2Btuin/hft2F 1.442 3 1011.442 3 10+11.442 3 1033.445 3 1041.240 3 1011.240 3 10+18.333 3 1021. 8.788 3 1012.232 3 10+1in/clo 1.641 3 1011.641 3 10+11.641 3 1033.920 3 1041.411 3 1011.411 3 1019.482 3 1021.138 1. 2.540 3 10+1mm/clo 6.461 3 1036.461 3 1016.461 3 1051.543 3 1055.5
27、56 3 1035.556 3 1013.733 3 1034.480 3 1033.937 3 1021.AUnits are given in terms of: (1) the absolute joule per second, or watt; (2) the calorie (International Table) = 4.1868 J; (3) the British thermal unit (InternationalTable) = 1055.06 J; and (4) the clo (unit of clothing resistance) = 0.155 Km2/W
28、.BRecommended (SI) units.TABLE 2 Conversion Factors for Thermal TransmittanceATo ConvertThermalTransmittanceMultiply byFromtoW/m2KBW/cm2K cal/scm2K kg-cal/hm2K Btu/hft2F clo1W/m2K 1. 1. 3 1042.388 3 1058.598 3 1011.761 3 1011.548 3 101W/cm2K 1. 3 10+41. 2.388 3 1018.598 3 10+31.761 3 10+31.548 3 10+
29、3cal/scm2K 4.187 3 10+44.187 1. 3.6 3 10+47.373 3 10+36.480 3 10+3kg-cal/hm2K 1.163 1.163 3 1042.778 3 1051. 2.048 3 1011.8 3 101Btu/hft2F 5.678 5.678 3 1041.356 3 1044.882 1. 8.788 3 101clo16.461 6.461 3 1041.543 3 1045.556 1.138 1.AUnits are given in terms of: (1) the absolute joule per second, or
30、 watt; (2) the calorie (International Table) = 4.1868 J; (3) the British thermal unit (InternationalTable) = 1055.06 J; and (4) the clo (unit of clothing resistance) = 0.155 Km2/W.BRecommended (SI) units.D 1518 85 (2003)2test method of this scope to establish details sufficient to coverall contingen
31、cies. Departures from the instructions of TestMethod D 1518 may lead to significantly different test results.Technical knowledge concerning the theory of heat flow,temperature measurement, and testing practices is needed toevaluate which departures from the instructions are significant.Standardizati
32、on of the method reduces, but does not eliminatethe need for such technical knowledge. Any significant depar-tures are to be reported with the results.4.3 Test Method D 1518 for the determination of the ther-mal transmittance of textile materials is considered satisfactoryfor acceptance testing of c
33、ommercial shipments of textilematerials because the test method has been used in the trade foracceptance testing. And it is the best test method known for thispurpose.4.3.1 In case of a dispute arising from differences inreported results when using Test Method D 1518 for accep-tance testing of comme
34、rcial shipments, the purchaser and thesupplier should conduct comparative tests to determine if thereis a statistical bias between their laboratories. Competentstatistical assistance is recommended for the investigation ofbias. As a minimum, the two parties should take a group of testspecimens which
35、 are as homogeneous as possible and whichare from a lot of material of the type in question. The testspecimens should then be sent to each laboratory for testing.The average results from the two laboratories should becompared using Students t-test for paired data and an accept-able probability level
36、 chosen by the two parties before testingis begun. If a bias is found, either its cause must be found andcorrected or the purchaser and the supplier must agree tointerpret future test results with consideration to the knownbias.TABLE 3 Conversion Factors for Thermal ResistivityATo ConvertThermalResi
37、stivityBMultiply byFromtomK/WBm2K/Wcm cmK/W cmKs/cal mKh/kg-calm2Kh/kg-calcmftFh/Btuft2Fh/Btuinclo/in clo/mmmK/W 1. 1. 3 1021. 3 10+24.187 3 10+21.163 1.163 3 1021.731 1.442 3 1011.641 3 1016.461 3 103m2K/Wcm1. 3 10+21. 1. 3 10+44.187 3 10+41.163 3 10+21.163 1.731 3 10+21.442 3 10+11.641 3 1016.461
38、3 101cmK/W 1. 3 1021. 3 1041. 4.187 1.163 3 1021.163 3 1041.731 3 1021.442 3 1031.641 3 1036.461 3 105cmKs/cal 2.388 3 1032.388 3 1052.388 3 1011. 2.778 3 1032.778 3 1054.134 3 1033.445 3 1043.920 3 1041.543 3 105mKh/kg-cal8.598 3 1018.598 3 1038.598 3 10+13.6 3 10+21. 1. 3 1021.488 1.240 3 1011.411
39、 3 1015.556 3 103m2Kh/kg-calcm8.598 3 10+18.598 3 1018.598 3 10+33.6 3 10+41. 3 10+21. 1.488 3 10+21.240 3 10+11.411 3 10+15.556 3 101ftFh/Btu 5.778 3 1015.778 3 1035.778 3 10+12.419 3 10+26.720 3 1016.720 3 1031. 8.333 3 1029.482 3 1023.733 3 103ft2Fh/Btuin6.934 6.934 3 1026.934 3 10+22.903 3 10+38
40、.064 8.064 3 1021.2 3 10+11. 1.138 4.480 3 103clo/in 6.093 6.093 3 1026.093 3 10+22.551 3 10+37.087 7.087 3 1021.055 3 10+18.788 3 1011. 3.937 3 102clo/mm 1.548 3 10+21.548 1.548 3 10+46.480 3 10+41.8 3 10+21.8 2.679 3 10+22.232 3 10+12.540 3 10+11.AUnits are given in terms of: (1) the absolute joul
41、e per second, or watt; (2) the calorie (International Table) = 4.1868 J; (3) the British thermal unit (InternationalTable) = 1055.06 J; and (4) the clo (unit of clothing resistance) = 0.155 Km2/W.BRecommended (SI) units.TABLE 4 Conversion Factors for Thermal ResistanceATo ConvertThermalResistanceMul
42、tiply byFromtom2K/WBcm2K/W cm2Ks/cal m2Kh/kg-cal ft2Fh/Btu clom2K/W 1. 1. 3 10+44.187 3 10+41.163 5.678 6.461cm2K/W 1. 3 1041. 4.187 1.163 3 1045.678 3 1046.461 3 104cm2Ks/cal 2.388 3 1052.388 3 1011. 2.778 3 1051.356 3 1041.543 3 104m2Kh/kg-cal 8.598 3 1018.598 3 10+33.6 3 10+41. 4.882 5.556ft2Fh/B
43、tu 1.761 3 1011.761 3 10+37.373 3 10+32.048 3 1011. 1.138clo 1.548 3 1011.548 3 10+36.480 3 10+31.8 3 1018.788 3 1011.AUnits are given in terms of: (1) the absolute joule per second, or watt; (2) the calorie (International Table) = 4.1868 J; (3) the British thermal unit (InternationalTable) = 1055.0
44、6 J; and (4) the clo (unit of clothing resistance) = 0.155 Km2/W.BRecommended (SI) units.TABLE 5 Miscellaneous Conversion FactorsPropertiesTo Convert froma Value Ex-pressed asTo a ValueExpressed asMultiply byMass per unit oz/yd2g/m233.91area mg/cm2g/m210.0Thickness in. mm 25.41/1000 in. (mil) mm 0.0
45、254Bulk density lb/ft3kg/m316.02(oz/yd2)/in kg/m31.335(g/m2)/mm kg/m31.0D 1518 85 (2003)35. Apparatus (Fig. 1, Fig. 2, and Fig. 3)NOTE 1The drawings and illustrations are intended as suggesteddesigns only. The final design of equipment, including necessary wiring,will be dictated by the choice of th
46、e electrical measuring and controlequipment.5.1 Hot PlateA guard ring flat plate composed of a testplate, guardring, and bottom plate as follows, each electricallymaintained at a constant temperature in the range of humanskin temperature 33 to 36C (91.4 to 98.8F).5.1.1 Test PlateThe test plate porti
47、on of the hot plate shallbe at least 150 mm (6.0 in.) square and shall be placed at thecenter of the upper surface of the hot-plate assembly. It shall bemade of aluminum or copper and painted a dull black toapproximate the emissivity of the human skin. The heatingelement shall consist of parallel wi
48、res, preferably of constantanmetal, insulated from, but mounted within 3 mm (0.1 in.) of theupper plate.5.1.2 Guard RingThe guard ring bordering the test plateshall be at least 63.5 mm (2.5 in.) in width and shall be of thesame thickness, composition, and type of construction as thetest plate. It sh
49、all be coplanar with the test plate, and shall beseparated from it by means of a strip of cork or other suitableinsulating material approximately 3-mm (0.1-in.) wide. Theguard ring shall be designed to prevent lateral loss of heat fromthe test plate.5.1.3 Bottom PlateThe bottom plate shall be of the samethickness, c
