ASTM_D_2157_-_94_2013.pdf

Designation:D215794(Reapproved 2013)Standard Test Method forEffect of Air Supply on Smoke Density in Flue Gases fromBurning Distillate Fuels1This standard is issued under the fixed designation D2157;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 evaluation of the perfor-mance of distillate fuels from the standpoint of clean,efficientburning.It is intended primarily for use with home heatingequipment burning No.1 or No.2 fuel oils.It can be usedeither in the laboratory or in the field to compare fuels using agiven heating unit or to compare the performance of heatingunits using a given fuel.NOTE1This test method applies only to pressure atomizing androtary-type burners.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.2.1 Arbitrary and relative units are also used.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:2D2156 Test Method for Smoke Density in Flue Gases fromBurning Distillate Fuels3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 effciencydefined as the percentage of gross heat ofcombustion of the fuel which is retained by the equipment andwhich does not pass out in the flue gases.3.1.2 excess combustion airthe percentage of air enteringthe equipment over and above that needed for stoichiometricconversion of the fuel to the ultimate combustion products,essentially CO2and water,for a normal fuel.This may becalculated from the percentage CO2in the flue gas and thecarbon-hydrogen ratio of the fuel.3.1.3 flue-gas carbon dioxide(CO2)the percentage con-centration of carbon dioxide in the flue gas,measured byconventional Orsat analysis,or the equivalent.3.1.4 net stack temperaturethe difference between thestack temperature and the ambient temperature of the air nearthe inlet to the burner.3.1.5 smoke densitythe concentration of smoke in the fluegas,measured as a Smoke Spot Number as described in TestMethod D2156.4.Summary of Test Method4.1 The flue-gas smoke density is measured for variousamounts of combustion air while the burner is operating atequilibrium conditions.Results are expressed as a plot ofsmoke density as a function of flue-gas carbon dioxide(CO2)content,or alternatively,as a function of percentage excesscombustion air.5.Significance and Use5.1 This test method relates efficiency of operation ofdomestic heating equipment to clean burning.Reducing com-bustion air in a burner gives more efficient operation.Theextent to which combustion air can be reduced is limited by theonset of unacceptable smoke production.By delineating therelation between smoke density and air supply,this test method(together with net stack temperature data)defines the maxi-mum efficiency for a given installation at any acceptable smokelevel.5.2 For certain types of equipment,such as the rotarywall-flame burner,too much excess air will cause smoke aswell as too little.For these cases,the point of minimum excessair at the acceptable smoke level indicates the optimumefficiency.5.3 The operating temperatures of the equipment will affectthese test results.The relation of excess air to smoke density is1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.E0 on Burner,Diesel,Non-Aviation Gas Turbine,and Marine Fuels.Current edition approved May 1,2013.Published August 2013.Originallyapproved in 1963.Last previous edition approved in 2008 as D2157 94(2008).DOI:10.1520/D2157-94R13.2For 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 thus susceptible to some change at different points in anoperating cycle.In practice,an adequate compromise is pos-sible by operating the burner for 15 min before any readingsare recorded and then obtaining the test data within a succeed-ing 25-min period.5.4 Under laboratory conditions,CO2readings are repro-ducible to 60.3%and smoke readings are reproducible to 612smoke spot number.6.Apparatus6.1 Sampling Device for determining smoke density,asdescribed in the Apparatus section of Test Me