ImageVerifierCode 换一换
格式:PDF , 页数:20 ,大小:206.06KB ,
资源ID:466916      下载积分:10000 积分
快捷下载
登录下载
邮箱/手机:
温馨提示:
如需开发票,请勿充值!快捷下载时,用户名和密码都是您填写的邮箱或者手机号,方便查询和重复下载(系统自动生成)。
如填写123,账号就是123,密码也是123。
特别说明:
请自助下载,系统不会自动发送文件的哦; 如果您已付费,想二次下载,请登录后访问:我的下载记录
支付方式: 支付宝扫码支付 微信扫码支付   
注意:如需开发票,请勿充值!
验证码:   换一换

加入VIP,免费下载
 

温馨提示:由于个人手机设置不同,如果发现不能下载,请复制以下地址【http://www.mydoc123.com/d-466916.html】到电脑端继续下载(重复下载不扣费)。

已注册用户请登录:
账号:
密码:
验证码:   换一换
  忘记密码?
三方登录: 微信登录  

下载须知

1: 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。
2: 试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓。
3: 文件的所有权益归上传用户所有。
4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
5. 本站仅提供交流平台,并不能对任何下载内容负责。
6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

版权提示 | 免责声明

本文(ASTM C518-2015 Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus《使用热流量计仪器测量稳态热传输性能的标准试验方法》.pdf)为本站会员(inwarn120)主动上传,麦多课文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知麦多课文库(发送邮件至master@mydoc123.com或直接QQ联系客服),我们立即给予删除!

ASTM C518-2015 Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus《使用热流量计仪器测量稳态热传输性能的标准试验方法》.pdf

1、Designation: C518 10C518 15Standard Test Method forSteady-State Thermal Transmission Properties by Means ofthe Heat Flow Meter Apparatus1This standard is issued under the fixed designation C518; the number immediately following the designation indicates the year oforiginal adoption or, in the case o

2、f revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This tes

3、t method covers the measurement of steady state thermal transmission through flat slab specimens using a heat flowmeter apparatus.1.2 The heat flow meter apparatus is used widely because it is relatively simple in concept, rapid, and applicable to a wide rangeof test specimens.The precision and bias

4、 of the heat flow meter apparatus can be excellent provided calibration is carried out withinthe range of heat flows expected. This means calibration shall be carried out with similar types of materials, of similar thermalconductances, at similar thicknesses, mean temperatures, and temperature gradi

5、ents, as expected for the test specimens.1.3 This a comparative, or secondary, method of measurement since specimens of known thermal transmission properties shallbe used to calibrate the apparatus. Properties of the calibration specimens must be traceable to an absolute measurement method.The calib

6、ration specimens should be obtained from a recognized national standards laboratory.1.4 The heat flow meter apparatus establishes steady state one-dimensional heat flux through a test specimen between twoparallel plates at constant but different temperatures. By appropriate calibration of the heat f

7、lux transducer(s) with calibrationstandards and by measurement of the plate temperatures and plate separation. Fouriers law of heat conduction is used to calculatethermal conductivity, and thermal resistivity or thermal resistance and thermal conductance.1.5 This test method shall be used in conjunc

8、tion with Practice C1045. Many advances have been made in thermal technology,both in measurement techniques and in improved understanding of the principles of heat flow through materials. These advanceshave prompted revisions in the conceptual approaches to the measurement of the thermal transmissio

9、n properties (1-4).2 All usersof this test method should be aware of these concepts.1.6 This test method is applicable to the measurement of thermal transmission through a wide range of specimen properties andenvironmental conditions. The method has been used at ambient conditions of 10 to 40C with

10、thicknesses up to approximately250 mm, and with plate temperatures from 195C to 540C at 25-mm thickness (5, 6).1.7 This test method may be used to characterize material properties, which may or may not be representative of actualconditions of use. Other test methods, such as Test Methods C236 or C97

11、6 should be used if needed.1.8 To meet the requirements of this test method the thermal resistance of the test specimen shall be greater than 0.10 m2K/Win the direction of the heat flow and edge heat losses shall be controlled, using edge insulation, or a guard heater, or both.1.9 It is not practica

12、l in a test method of this type to try to establish details of construction and procedures to cover allcontingencies that might offer difficulties to a person without pertinent technical knowledge. Thus users of this test method shallhave sufficient knowledge to satisfactorily fulfill their needs. F

13、or example, knowledge of heat transfer principles, low levelelectrical measurements, and general test procedures is required.1.10 The user of this method must be familiar with and understand the Annex. The Annex is critically important in addressingequipment design and error analysis.1.11 Standardiz

14、ation of this test method is not intended to restrict in any way the future development of improved or newmethods or procedures by research workers.1 This test method is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.30 on Ther

15、malMeasurement.Current edition approved May 1, 2010Sept. 1, 2015. Published June 2010December 2015. Originally approved in 1963. Last previous edition approved in 20042010 asC518 04.C518 10. DOI: 10.1520/C0518-10.10.1520/C0518-15.2 The boldface numbers in parentheses refer to the list of references

16、at the end of this test method.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommen

17、ds that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.12 Since the de

18、sign of a heat flow meter apparatus is not a simple matter, a procedure for proving the performance of anapparatus is given in Appendix X3.1.13 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.14 This standard does not purpor

19、t to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to consult and establish appropriate safety and health practices and determine the applicability ofregulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standa

20、rds:3C167 Test Methods for Thickness and Density of Blanket or Batt Thermal InsulationsC168 Terminology Relating to Thermal InsulationC177 Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of theGuarded-Hot-Plate ApparatusC236 Test Method for Steady-Sta

21、te Thermal Performance of BuildingAssemblies by Means of a Guarded Hot Box (Withdrawn2001)4C687 Practice for Determination of Thermal Resistance of Loose-Fill Building InsulationC976 Test Method for Thermal Performance of Building Assemblies by Means of a Calibrated Hot Box (Withdrawn 2002)4C1045 Pr

22、actice for Calculating Thermal Transmission Properties Under Steady-State ConditionsC1046 Practice for In-Situ Measurement of Heat Flux and Temperature on Building Envelope ComponentsC1058 Practice for Selecting Temperatures for Evaluating and Reporting Thermal Properties of Thermal InsulationC1114

23、Test Method for Steady-State Thermal Transmission Properties by Means of the Thin-Heater ApparatusC1363 Test Method for Thermal Performance of Building Materials and EnvelopeAssemblies by Means of a Hot BoxApparatusE230E230/E230M Specification and Temperature-Electromotive Force (EMF)(emf) Tables fo

24、r Standardized ThermocouplesE178 Practice for Dealing With Outlying ObservationsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 ISO Standard:ISO 8301:1991 Thermal InsulationDetermination of Steady

25、-State Thermal Resistance and Related PropertiesHeat FlowMeter Apparatus53. Terminology3.1 DefinitionsFor definitions of terms and symbols used in this test method, refer to Terminology C168 and to the followingsubsections.3.2 Definitions of Terms Specific to This Standard:3.2.1 calibration, nthe pr

26、ocess of establishing the calibration factor for a particular apparatus using calibration specimenshaving known thermal transmission properties.3.2.2 calibration transfer specimen, n(CTS) a thermal calibration specimen that has been measured by a national standardslaboratory (7).3.2.3 cold surface a

27、ssembly, nthe plate that provides as isothermal boundary at the cold surface of the test specimen(s).3.2.4 controlled environment, nan environment sometimes employed in the apparatus to limit lateral heat flows.3.2.5 edge insulation, nauxiliary insulation used to limit lateral heat flows, these are

28、sometimes permanently mounted in theapparatus.3.2.6 guard, npromotes one-dimensional heat flow. Primary guards are planar, additional coplanar guards can be used andsecondary or edge guards are axial.3.2.7 heat flow meter apparatus, nthe complete assemblage of the instrument, including hot and cold

29、isothermal surfaces, theheat flux transducer(s), and the controlled environment if used, and instrumentation to indicate hot and cold surface temperatures,specimen thickness, and heat flux.3.2.8 hot surface assembly, nthe plate that provides an isothermal boundary at the hot surface of the test spec

30、imen(s).3.2.9 heat flux transducer, na device containing a thermopile, or an equivalent, that produces an output which is a functionof the heat flux passing through it. The metering area usually consists of a number of differently connected temperature sensors3 For referencedASTM standards, visit th

31、eASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 The last approved version of this historical standard is referenced on www.astm.org.5 Available fro

32、m American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.C518 152placed on each face of a core and surface sheets to protect the assembly. A properly designed transducer will have a sensitivitythat is essentially independent of the thermal pro

33、perties of the specimen.3.2.10 metering area, nthe area of the specimen(s) in contact with the sensor area of the heat flux transducer.3.2.11 secondary transfer standard, na specimen, which has been measured in a heat flow meter apparatus, which has beencalibrated with primary standards, used to cal

34、ibrate additional apparatuses.3.2.12 sensitivity, nthe ratio of the heat flux passing through the transducer to the electrical output of the heat flux transducer.3.2.13 standard reference material (SRM), na lot of material that has been characterized by a national standards laboratory(7).3.2.14 ther

35、mal transmission properties, nthose properties of a material or system that define the ability of the material orsystem to transfer heat. Properties, such as thermal resistance, thermal conductance, thermal conductivity, and thermal resistivitywould be included, as defined in Terminology C168.3.3 Sy

36、mbols and UnitsThe symbols used in this test method have the following significance:3.3.1 thermal conductivity, W/(mK).3.3.2 Cthermal conductance, W/(m2K)3.3.3 Rthermal resistance, (m2K)/W.3.3.4 qheat flux (heat flow rate, Q, through area A), W/m2.3.3.5 Qheat flow rate in the metered area, W.3.3.6 A

37、metering area, m2.3.3.7 Lseparation between the hot and cold plate assemblies during testing, m.3.3.8 Tmmean temperature, (Th + Tc)/2, K.3.3.9 Ttemperature difference across the specimen, K.3.3.10 (bulk) density of the material tested, kg/m3.3.3.11 Scalibration factor of the heat flux transducer, (W

38、/m2)/V.3.3.12 Eheat flux transducer output, V.3.3.13 Thtemperature of the hot plate surface, K.3.3.14 Tctemperature of the cold plate surface, K.3.4 Subscripts:3.4.1 hhot.3.4.2 ccold3.4.3 a, bfirst and second specimen.3.4.4 mmean.3.4.5 statistical term used to define significance level.4. Significan

39、ce and Use4.1 This test method provides a rapid means of determining the steady-state thermal transmission properties of thermalinsulations and other materials with a high level of accuracy when the apparatus has been calibrated appropriately.4.2 Proper calibration of the heat flow meter apparatus r

40、equires that it be calibrated using specimen(s) having thermaltransmission properties determined previously by Test Methods C177, or C1114.NOTE 1Calibration of the apparatus typically requires specimens that are similar to the types of materials, thermal conductances, thicknesses, meantemperatures,

41、and temperature gradients as expected for the test specimens.4.3 The thermal transmission properties of specimens of a given material or product may vary due to variability of thecomposition of the material; be affected by moisture or other conditions; change with time; change with mean temperature

42、andtemperature difference; and depend upon the prior thermal history. It must be recognized, therefore, that the selection of typicalvalues of thermal transmission properties representative of a material in a particular application should be based on a considerationof these factors and will not appl

43、y necessarily without modification to all service conditions.4.3.1 As an example, this test method provides that the thermal properties shall be obtained on specimens that do not containany free moisture although in service such conditions may not be realized. Even more basic is the dependence of th

44、e thermalproperties on variables, such as mean temperature and temperature difference. These dependencies should be measured or the testmade at conditions typical of use.4.4 Special care shall be taken in the measurement procedure for specimens exhibiting appreciable inhomogeneities,anisotropies, ri

45、gidity, or especially high or low resistance to heat flow (see Practice C1045). The use of a heat flow meter apparatuswhen there are thermal bridges present in the specimen may yield very unreliable results. If the thermal bridge is present andparallel to the heat flow the results obtained may well

46、have no meaning. Special considerations also are necessary when themeasurements are conducted at either high or low temperatures, in ambient pressures above or below atmospheric pressure, or inspecial ambient gases that are inert or hazardous.C518 1534.5 The determination of the accuracy of the meth

47、od for any given test is a function of the apparatus design, of the relatedinstrumentation, and of the type of specimens under test (see Section 10), but this test method is capable of determining thermaltransmission properties within 6 2 % of those determined by Test Method C177 when the ambient te

48、mperature is near the meantemperature of the test (T (ambient) = T (mean) 6 1C), and in the range of 10 to 40C. In all cases the accuracy of the heat flowmeter apparatus can never be better than the accuracy of the primary standards used to calibrate the apparatus.4.5.1 When this test method is to b

49、e used for certification testing of products, the apparatus shall have the capabilities requiredin A1.7 and one of the following procedures shall be followed:4.5.1.1 The apparatus shall have its calibration checked within 24 h before or after a certification test using either secondarytransfer standards traceable to, or calibration standards whose values have been established by, a recognized national standardslaboratory not more than five years prior to the certification date. The average of two calibrations shall be used a

copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1