ASTM_D_2717_-_95_2009.pdf

Designation:D271795(Reapproved 2009)Standard Test Method forThermal Conductivity of Liquids1This standard is issued under the fixed designation D2717;the number immediately following the 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 determination of the thermalconductivity of nonmetallic liquids.It is applicable to liquidsthat are:(1)chemically compatible with borosilicate glass andplatinum;(2)moderately transparent or absorbent to infraredradiation;and(3)have a vapor pressure less than 200 torr at thetemperature of test.1.1.1 Materials that have vapor pressures of up to 345 kPa(50 psia),absolute can be tested provided that adequatemeasures are taken to repress volatilization of the sample bypressurizing the thermal conductivity cell.The usual safetyprecautions for pressure vessels shall be followed under thesecircumstances.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D86 Test Method for Distillation of Petroleum Products atAtmospheric PressureD1160 Test Method for Distillation of Petroleum Products atReduced PressureD2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas ChromatographyD2893 Test Methods for Oxidation Characteristics ofExtreme-Pressure Lubrication Oils3.Terminology3.1 Units:3.1.1 The energy units used in this test method are definedas follows:1 Cal(International Table calorie)=4.1868 absolute J1 Btu(British thermal unit)=1055.07 absolute J3.1.2 The units of thermal conductivity commonly used andtheir interconversion factors are shown in Table 1.3.2 For working purposes in this test method,the rounded-off value of 4.19 J/cal is used,as this is adequate for theprecision of the test and also represents the rounded-off valueof watt-second per calorie units in Table 1,thus avoiding thedifficulty caused by the dual definition of the calorie.3.3 Symbols:Tf=filament temperature,C,Tb=bath thermostat temperature,C,T=Tf Tb,C,rf=filament radius,cm,ri=internal radius of tube,cm,ro=external radius of tube,cm,L=effective length of tube,cm,R=resistance of filament,I=electric current through filament,A,KL=thermal conductivity of liquid,cal/scmC,KG=thermal conductivity of glass-tube,cal/scmC,A=ln(ri/rf)/2 L,cm1,andB=ln(ro/ri)/2 L KG,sC/cal.4.Summary of Test Method4.1 A thermal conductivity cell consisting of a straight,four-lead,platinum resistance thermometer element locatedconcentrically in a long,small-diameter,precision-bore boro-silicate glass tube is calibrated by accurate measurement of thecell dimensions and by determination of the temperature-resistance properties of the platinum element.4.2 Thermal conductivity is determined by measurement ofthe temperature gradient produced across the liquid sample bya known amount of energy introduced into the cell by electri-cally heating the platinum element.5.Significance and Use5.1 The thermal conductivity of a substance is a measure ofthe ability of that substance to transfer energy as heat in the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.L0.07 on Engineering Sciences of High Performance Fluids andSolids(Formally D02.1100).Current edition approved Oct.1,2009.Published November 2009.Originallyapproved in 1968.Last previous edition approved in 2005 as D271795(2005).DOI:10.1520/D2717-95R09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume 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 States1 absence of mass transport phenomena.It is used in engineeringcalculations that relate to the manner in which a given systemcan react to thermal stresses.6.Apparatus6.1 Thermal Conductivity Cell,consists essentially of a thin,straight platinum filament sealed axially in a borosilicate glasstube.The filament is held taut by a platinum spring.Two heavygage platinum studs support the filament at either end andpermit the filament itself to serve as the element and a four-leadplatinum resistance thermometer.Details and cell constructionare shown in Fig.1.6.1.1 A tube of 5.00 6 0.01 mm inside diameter shall beused for liquids of low viscosity as these may creat