Examination is made of the operational limits in two variable compression-ratio single-cylinder engines when operating on the gaseous fuels methane, propane, LPG, and hydrogen under a wide range of conditions. Two definitions for the limits were employed. The first was associated with the first detectable misfire on leaning the mixture, while the second was the first detectable firing under motoring condition in the presence of a spark when the mixture was being enriched slowly. Attempts were also made to relate these limits to the corresponding values for quiescent conditions reckoned on the basis of the flammability limits evaluated at the mean temperature and pressure prevailing within the cylinder charge at the time of the spark. The measured limits in the engine were always higher than the corresponding flammability limit values for the three fuels. Both of these limits appear to correlate reasonably well with the calculated mean temperature of the mixture at the time of passing the spark.

Issue Section:
Technical Papers
Topics:
Compression, Cylinders, Engines, Firing, Fuels, Gaseous fuels, Hydrogen, Methane, Pressure, Single-cylinder engines, Spark-ignition engine, Temperature
1.
Al-Alousi, Y., and Karim, G. A., 1984, “Some Considerations of Cyclic Variations in Spark Ignition Engines Fuelled with Gaseous Fuels,” SAE Paper No. 840232.
2.
Anderson, R. W., and Asik, J. R., 1983, “Ignitability Experiments in a Fast Burn, Lean Burn Engine,” SAE Paper No. 830477.
3.
Annand
W. J. D.
,
1963
, “
Heat Transfer in the Cylinders of a Reciprocating Internal Combustion Engine
,”
Proceedings of Institute of Mechanical Engineers
, Vol.
77
, p.
973
973
.
4.
Barton, R. K., 1970, “Cycle-by-Cycle Variations of a Spark Ignition Engine,” SAE Paper No. 700488.
5.
Coward, H. F., and Jones, G. W., 1952, “Limits of Flammability of Gases and Vapors,” U.S. Bureau of Mines Bulletin 503.
6.
Durbin, E., and Tsai, K., 1983, “Extending the Lean Limit Operation of an S.I. Engine with Multiple Electrode Spark Plug,” SAE Paper No. 830476.
7.
Karim
G. A.
, and
Klat
S. R.
,
1966
, “
The Knock and Autoignition Characteristics of Some Gaseous Fuels and Their Mixtures
,”
Journal of the Institute of Fuel
, Vol.
39
, Mar., pp.
109
–
119
.
8.
Karim, G. A., and Wierzba, I., 1989, “Experimental and Analytical Studies of the Lean Operational Limits in Methane Fuelled Spark Ignition and Compression Ignition Engines,” SAE Paper No. 891637.
9.
Karim, G. A., and Gao, J., 1993, “Prediction of the Performance of Spark Ignition Gas Engines Including Knock,” SAE Paper No. 932823.
10.
Quader, A. A., 1974, “Lean Combustion and the Misfire Limit in S.I. Engines,” SAE Paper No. 41055.
11.
Quader, A. A., 1976, “What Limits Lean Operation in S.I. Engines—Flame Initiation or Propagation,” SAE Paper No. 760760.
12.
Ryan, T. W., Lestz, S. S., and Meyer, E., 1974, “Extension of the Lean Misfire Limit and Reduction of Exhaust Emissions of an S.I. Engine by Modification of Ignition and Intake Systems,” SAE Paper No. 740105.
13.
Tanuma, T., Sasaki, K., Kaneko, T., and Kawasaki, H., 1971, “Ignition, Combustion, and Exhaust Emission of Lean Mixtures in Automotive S.I. Engines,” SAE Paper No. 710159.
14.
Wierzba
I.
, and
Karim
G. A.
,
1990
, “
A Predictive Approach for the Flammability Limits of Methane-Nitrogen Mixtures
,”
ASME JOURNAL OF ENERGY RESOURCES TECHNOLOGY
, Vol.
112
, pp.
251
–
253
.
15.
Winsor, R. E., and Patterson, D. J., 1973, “Mixture Turbulence—A Key to Cyclic Combustion Variation,” SAE Paper No. 730086.
16.
Zabetakis, M. J., 1965, “Flammability Characteristics of Combustible Gases and Vapors,” Bureau of Mines, Bulletin 627.
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