Experiments with an inshot burner used in residential natural gas furnaces are presented. The concentrations of NOx, NO, and CO in the combustion products of partially aerated natural gas flames were measured in a laboratory combustion chamber. When the conventional circular venturi inlet of the inshot burner was replaced by elliptic venturi inlets, an increase of up to 30 percent in the primary-air entrainment and a decrease of up to 20 percent in the NOx emission index were observed. Temperature field measurements in the flames were in conformity with the emission index measurements.

Issue Section:
Research Papers
Topics:
Furnaces, Emissions, Flames, Natural gas, Nitrogen oxides, Venturi tubes, Combustion, Combustion chambers, Temperature
1.
Beer, J. M., and Chigier, N. A., 1972, Combustion Aerodynamics, Halstead Press, New York, NY.
2.
Fristrom, R. M., and Westenberg, A. A., 1965, Flame Structure, McGraw-Hill Publications, New York, NY.
3.
Gollahalli
S. R.
,
Khanna
T.
, and
Prabhu
N.
,
1992
, “
Diffusion Flames of Gas Jets Issued from Circular and Elliptic Nozzles
,”
Combustion Science and Technology
, Vol.
86
, pp.
267
–
290
.
4.
Gollahalli, S. R., 1992, “Research on Combustion Processes Relevant to Burners in HVAC Systems,” Annual Progress Report, submitted to Gas Research Institute, Chicago, IL.
5.
Gutmark, E., and Ho, C. M., 1983, “Near Field Pressure Fluctuations of an Elliptic Jet,” AIAA Paper No. 83-0663.
6.
Gutmark, E., Schadow, K. C., Parr, D. M., Harris, C. K., and Wilson, K. J., 1985, “The Mean and Turbulent Structure of Noncircular Jets,” AIAA Paper No. 85-0543.
7.
Gutmark
E.
, and
Ho
C. M.
,
1986
, “
Visualization of a Forced Elliptic Jet
,”
AIAA Journal
, Vol.
24
, pp.
684
–
685
.
8.
Gutmark, E., Schadow, K. C., and Wilson, K. J., 1987, “Noncircular Jet Dynamics in Supersonic Combustion,” AIAA Paper No. 87-1878.
9.
Hargreaves, K. J. A., Harvey, R., and Roper, G., and Smith, D. B., 1981, “Formation of NO2 by Laminar Flames,” Eighteenth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA., pp. 133–142.
10.
Ho
C. M.
, and
Gutmark
E.
,
1987
, “
Vortex Induction and Mass Entrainment in a Small Aspect Ratio Elliptic Jet
,”
Journal of Fluid Mechanics
, Vol.
179
, pp.
383
–
405
.
11.
Hori, M., 1986, “Experimental Study of Nitrogen Dioxide Formation in Combustion Systems,” Twenty-first Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA., pp. 1181–1188.
12.
Hussain
F.
, and
Hussain
H. S.
 Elliptic Jets. Part 1,
1989
, “
Characteristics of Excited and Unexcited Jets
,”
Journal of Fluid Mechanics
, Vol.
208
, pp.
257
–
320
.
13.
Kolluri, P., 1992, “Application of Elliptical Primary-Air Inlet Geometries in the Inshot Burners of Residential Gas Furnaces,” M. S. thesis, School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, OK.
14.
Prabhu, N., 1989, “Gas Jet Flames Over Elliptic Nozzles,” M. S. thesis, School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, OK.
15.
Prabhu, N., and Gollahalli, S. R., 1989, “Comparison of Gas Jet Flames Over Circular and Elliptic Nozzles,” paper presented in Western States Section/Combustion Institute Meeting, Pullman, WA, Mar.
16.
Quinn, W. R., 1989, “The Turbulent Free Jet Issuing from a Sharp-Edged Elliptical Slot,” AIAA Paper 89-0664.
17.
Schadow, K. C., Wilson, K. J., Lee, M. J., and Gutmark, E., 1984, “Enhancement of Mixing in Ducted Rockets with Elliptic Gas-generator Nozzles,” AIAA Paper No. 84-1260.
18.
Schadow, K. C., Wilson, K. J., Parr, D. M., and Gutmark, E., 1986, “Mixing Characteristics of a Ducted Elliptical Jet with Dump,” AIAA Paper No. 86-1399.
19.
Schenck, Jr. H., 1961, Theories of Engineering Experimentation, McGraw-Hill Book Company, New York, NY.
20.
Sforza
P. M.
,
Steiger
M. H.
, and
Trentacoste
N.
,
1966
, “
Studies on Three-Dimensional Viscous Jets
,”
AIAA Journal
, Vol.
4
, pp.
800
–
806
.
21.
Trentacoste
N.
, and
Sforza
P.
,
1967
, “
Further Experimental Results for Three-Dimensional Free Jets
,”
AIAA Journal
, Vol.
5
, pp.
885
–
891
.
22.
Turns
S. R.
, and
Lovett
J. A.
,
1989
, “
Measurements of Oxides of Nitrogen Emissions From Turbulent Propane Jet Diffusion Flames
,”
Combustion Science and Technology
, Vol.
66
, pp.
233
–
249
.
23.
Turns
S. R.
, and
Myhr
F. H.
,
1991
, “
Oxides of Nitrogen Emissions from Turbulent Jet Flames: Part I—Fuel Effects and Flame Radiation
,”
Combustion and Flame
, Vol.
87
, pp.
319
–
335
.
This content is only available via PDF.
Copyright © 1996
 by The American Society of Mechanical Engineers
You do not currently have access to this content.