Designation:D4868−00(Reapproved2010)StandardTestMethodforEstimationofNetandGrossHeatofCombustionofBurnerandDieselFuels1ThisstandardisissuedunderthefixeddesignationD4868;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThistestmethodcoverstheestimationofthegrossandnetheatofcombustioninSIunits,megajoulesperkilogram,ofpetroleumfuelsfromthefueldensity,sulfur,water,andashcontent.NOTE1—TheequationforestimationofnetandgrossheatofcombustionusedinthismethodwereoriginallypublishedbytheNISTPublicationNo.97.1.2Thistestmethodisespeciallyusefulforestimating,usingaminimumnumberoftests,theheatofcombustionofburneranddieselfuelsforwhichitisnotusuallycriticaltoobtainverypreciseheatdeterminations.NOTE2—Moreaccurateestimationmethodsareavailableforaviationfuels(TestMethodsD1405,D4529,andD3338).However,thoseestima-tionmethodsrequireadditionalteststothoserequiredinthistestmethod.1.3Thistestmethodispurelyempirical(Note1).ItisapplicableonlytoliquidhydrocarbonfuelsderivedbynormalrefiningprocessesfromconventionalcrudeoilthatconformtotherequirementsofspecificationsforpetroleumfuelsasdescribedinNote3.Thistestmethodisvalidforthosefuelsinthedensityrangefrom750to1000kg/m3andthosethatdonotcontainanunusuallyhigharomaticcontent.Higharomaticcontentfuelswillnotnormallymeetfuelspecificationcriteria.NOTE3—Theestimationoftheheatofcombustionofahydrocarbonfuelfromitsdensityandsulfur,water,andashcontentisjustifiableonlywhenthefuelbelongstowell-definedclassesforwhicharelationshipbetweenthesequantitieshavebeenderivedfromaccurateexperimentalmeasurementsonrepresentativesamplesoftheseclasses.Evenintheseclasses,thepossibilitythattheestimatemaybeinerrorbylargeamountsforindividualfuelsshouldberecognized.Thistestmethodhasbeentestedforalimitednumberoffuelsfromoilsandbitumenandshaleoiloriginandhasbe...
