Designation:D7265−12(Reapproved2018)StandardSpecificationforHydrogenThermophysicalPropertyTables1ThisstandardisissuedunderthefixeddesignationD7265;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thethermophysicalpropertytablesfornormalhydro-genareforuseinthecalculationofthepressure-volume-temperature(PVT),thermodynamic,andtransportpropertiesofhydrogenforprocessdesignandoperations,particularlyastheyrelatetohydrogenfuelcellapplications.Tablesareprovidedforgaseoushydrogenattemperaturesbetween50Kand500Katpressuresto50MPa.ThesetablesweredevelopedbytheNationalInstituteofStandardsandTechnologyfromaStandardReferenceDatabaseproductREFPROP,version9.0.1.2Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.Applicability2.1Thesetablesapplydirectlyonlytopuregaseoushydro-gen.However,itisexpectedthattheymayfindsubstantialuseinmathematicalmodelsandtablesforthethermophysicalpropertiesofmixturescontaininghydrogen.3.Tables3.1Thetabulatedthermophysicalpropertiesare:ρ,molardensity(mol·L-1)V,molarvolume(L-1·mol)H,molarenthalpy(J·mol-1)S,molarentropy(J·K-1·mol-1)Cv,constantvolumemolarheatcapacity(J·K-1·mol-1)Cp,constantpressuremolarheatcapacity(J·K-1·mol-1)c,speedofsound(m·s-1)η,viscosity(µPa·s)λ,thermalconductivity(mW·m-1·K-1)3.2Thesetableswereproducedbyequationsfromacom-puterpackage,“NISTStandardReferenceDatabase23;Ref-erenceFluidThermodynamicandTransportPropertiesData-base(REFPROP):Version9.0.”Awideselectionofunits(SIunits,engineeringunits,chemicalunits)isavailablewiththisprogram.4.AdditionalInformation4.1Acomprehensiveeq...
