1、Designation:D789619Standard Test Method forThermal Conductivity,Thermal Diffusivity,and VolumetricHeat Capacity of Engine Coolants and Related Fluids byTransient Hot Wire Liquid Thermal Conductivity Method1This standard is issued under the fixed designation D7896;the number immediately following the
2、 designation indicates the year oforiginal adoption or,in the case of 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.1.Scope1.1 This test method covers the use
3、of a transient hot wireliquid thermal conductivity method and associated equipment(the System)for the determination of thermal conductivity,thermal diffusivity and volumetric heat capacity of aqueousengine coolants,non-aqueous engine coolants,and relatedfluids.The System is intended for use in a lab
4、oratory.1.2 The System directly measures thermal conductivity andthermal diffusivity without the requirement to input anyadditional properties.Volumetric heat capacity is calculated bydividing the thermal conductivity by the thermal diffusivity ofthe sample measured.1.3 This test method can be appli
5、ed to any aqueous ornon-aqueous engine coolants or related fluid with thermalconductivity in the range of 0.1 to 1.0 W/mK.1.4 This test method excludes fluids that react with plati-num.1.5 The range of temperatures applicable to this test methodis 20 to 100 C.1.6 This test method requires a sample o
6、f approximately 40mL.1.7 The System may be used without external pressurizationfor any fluid having a vapor pressure of 33.8 kPa(4.9 psia)orless at the test temperature.1.8 For a fluid having a vapor pressure greater than 33.8 kPa(4.9 psia)at the test temperature,external pressurization isrequired(s
7、ee Annex A2).1.9 The values stated in SI units are to be regarded asstandard.The values given in parentheses after SI units areprovided for information only and are not considered standard.1.10 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is t
8、heresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.11 This international standard was developed in accor-dance with internationally recognized principles on standa
9、rd-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1176 Practice for Sampling and Preparing Aqueous S
10、olu-tions of Engine Coolants orAntirusts for Testing PurposesD5931 Test Method for Density and Relative Density ofEngine Coolant Concentrates and Aqueous Engine Cool-ants by Digital Density MeterE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Termino
11、logy3.1 Definitions of Thermal Related Units:3.1.1 density(),nthe mass per unit volume of a sub-stance under specific conditions of pressure and temperature.Unit:kg/m3.3.1.2 specific heat capacity(Cp),nthe amount of heatrequired to raise the temperature of a unit mass of material by1 C.See Annex A1.
12、Unit:J/(kgK).3.1.3 thermal conductivity(),nrate of heat flow understeady conditions through unit area,per unit temperaturegradient in the direction perpendicular to the area.Unit:W/mK.3.1.4 thermal diffusivity(),na measure of the ability of asubstance to transmit a difference in temperature.Unit:m2/
13、s.3.1.5 volumetric heat capacity(VHC),nthe amount ofheat required to raise the temperature of a unit volume of1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids,and is the direct responsibility of SubcommitteeD15.22 on Non-Aqueous Coolants.Current
14、edition approved June 1,2019.Published June 2019.Originallyapproved in 2014.Last previous edition approved in 2014 as D789614.DOI:10.1520/D789619.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards vol
15、ume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardiz
16、ation established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 material by 1 C.Volumetric heat capacity is the thermalconductivity of a material divided by its thermal diffusivity.Unit:J/m3K.3.2 Definitions of Terms Specific to This Standard:3.2.1 transient hot wire method,na method for measure-ment of thermal properties wherein a thin wire is immersed ina
