ASTM D2157-94(2008)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D2157 − 94(Reapproved 2008)
Standard Test Method for
Effect of Air Supply on Smoke Density in Flue Gases from
Burning Distillate Fuels
This standard is issued under the fixed designation D2157; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.2 excess combustion air—the percentage of air entering
the equipment over and above that needed for stoichiometric
1.1 This test method covers the evaluation of the perfor-
conversion of the fuel to the ultimate combustion products,
mance of distillate fuels from the standpoint of clean, efficient
essentially CO and water, for a normal fuel. This may be
burning. It is intended primarily for use with home heating
calculated from the percentage CO in the flue gas and the
equipment burning No. 1 or No. 2 fuel oils. It can be used
carbon-hydrogen ratio of the fuel.
either in the laboratory or in the field to compare fuels using a
3.1.3 flue-gas carbon dioxide (CO )—the percentage con-
given heating unit or to compare the performance of heating
centration of carbon dioxide in the flue gas, measured by
units using a given fuel.
conventional Orsat analysis, or the equivalent.
NOTE 1—This test method applies only to pressure atomizing and
3.1.4 net stack temperature—the difference between the
rotary-type burners.
stack temperature and the ambient temperature of the air near
1.2 The values stated in inch-pound units are to be regarded
the inlet to the burner.
as standard. The values given in parentheses are mathematical
3.1.5 smoke density—the concentration of smoke in the flue
conversions to SI units that are provided for information only
gas, measured as a Smoke Spot Number as described in Test
and are not considered standard.
Method D2156.
1.2.1 Arbitrary and relative units are also used.
1.3 This standard does not purport to address all of the
4. Summary of Test Method
safety concerns, if any, associated with its use. It is the
4.1 The flue-gas smoke density is measured for various
responsibility of the user of this standard to establish appro-
amounts of combustion air while the burner is operating at
priate safety and health practices and determine the applica-
equilibrium conditions. Results are expressed as a plot of
bility of regulatory limitations prior to use.
smoke density as a function of flue-gas carbon dioxide (CO )
2. Referenced Documents content, or alternatively, as a function of percentage excess
combustion air.
2.1 ASTM Standards:
D2156 Test Method for Smoke Density in Flue Gases from
5. Significance and Use
Burning Distillate Fuels
5.1 This test method relates efficiency of operation of
domestic heating equipment to clean burning. Reducing com-
3. Terminology
bustion air in a burner gives more efficient operation. The
3.1 Definitions of Terms Specific to This Standard:
extent to which combustion air can be reduced is limited by the
3.1.1 effıciency—defined as the percentage of gross heat of
onset of unacceptable smoke production. By delineating the
combustion of the fuel which is retained by the equipment and
relation between smoke density and air supply, this test method
which does not pass out in the flue gases.
(together with net stack temperature data) defines the maxi-
mumefficiencyforagiveninstallationatanyacceptablesmoke
level.
This test method is under the jurisdiction of ASTM Committee D02 on
5.2 For certain types of equipment, such as the rotary
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee
D02.E0 on Burner, Diesel, Non-Aviation Gas Turbine, and Marine Fuels.
wall-flame burner, too much excess air will cause smoke as
Current edition approved Dec. 1, 2008. Published February 2009. Originally
well as too little. For these cases, the point of minimum excess
approved in 1963. Last previous edition approved in 2003 as D2157–94(2003).
air at the acceptable smoke level indicates the optimum
DOI: 10.1520/D2157-94R08.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or efficiency.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
5.3 The operating temperatures of the equipment will affect
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. these test results. The relation of excess air to smoke density is
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D2157 − 94 (2008)
thus susceptible to some change at different points in an
operating cycle. In practice, an adequate compromise is pos-
sible by operating the burner for 15 min before any readings
are recorded and then obtaining the test data within a succeed-
ing 25-min period.
5.4 Under laboratory conditions, CO readings are repro-
ducible to 60.3 % and smoke readings are reproducible to 6 ⁄2
smoke spot number.
6. Apparatus
6.1 Sampling Device for determining smoke density, as
FIG. 1 Typical Smoke-CO and Excess Air-CO Curves
2 2
described in the Apparatus
...