ASTMD39479207595100535359256=(CTbDesignation:D3947-92AMERICANSOCIETYFORTESTINGANDMATERIALS1916RaceStPhiladelphia,Pa19103ReprintedfromtheAnnualBwkofASTMStandards.CopyrightASTMIfnotlistedinthecurrentcombinedIndex,willappearinthene>bedition.StandardTestMethodforSpecificHeatofAircraftTurbineLubricantsbyThermalAnalysis'ThisstandardisissuedunderthefixeddesignationD3947;thenumberimmedittelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthescsindicatestheyearoflastreapproval.Asuperscriptcpsilon(clindicatesancditorialchangcsinccthelastrcvisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationofthespecificheatofoilbydifferentialscanningcalorimetry(DSC).1.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesinparenthesesareforinformationonly.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyproblems,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Foraspecifichazardstatement,seeNote1.2.Terminology2.1DtJnition:2.1.1speciJicheat,s,n-ameasureoftheamountofenergyrequiredtoproduceagiventemperaturechangewithinaunitquantityofthatsubstance.3.SummaryofTestMethod3.1Valuesforspecificheatsofoilsaredeterminedbythefollowingtwo-stepprocedure.Thedifferentialscanningcal-orimeterisprogrammedfirsttoheatanempty,unsealedsamplepanoverthedesiredtemperaturerangewhilemoni-toringtheheatsuppliedasafunctionoftemperature.Theprogramisrepeatedforthehermeticallysealedsamplepancontainingaweighedsampleofoil.Thespecificheatoftheoiliscalculatedfrohthedifferencebetweenthesetwosetsofmeasurements.3.2Apurematerialwithpublishedspecificheatvalues(forexample,diphenylether)isusedasacalibrationstan-dard.Calibrationscansaremadeunderthesameexperi-mentalconditionsasareusedfortheoilsamples.4.SignificanceandUse4.1Thespecificheatorheatcapacityofasubstanceisathermodynamicproperty.Itisusedinengineeringcalcula...
