The goal of this two-part paper is to develop a methodology using the variation of the measured crankshaft speed to calculate the mean indicated pressure (MIP) of a multicylinder engine and to detect cylinders that are lower contributors to the total engine output. Both the gas pressure torque and the crankshaft’s speed are, under steady-state operating conditions, periodic functions of the crank angle and may be expressed by Fourier series. For the lower harmonic orders, the dynamic response of the crankshaft approaches the response of a rigid body and that makes it is possible to establish correlations between the amplitudes and phases of the corresponding harmonic orders of the crankshaft’s speed and of the gas pressure torque. The inherent cycle-to-cycle variation in the operation of the cylinders requires a statistical approach to the problem. The first part of the paper introduces the statistical model for a harmonic component of the gas pressure torque and determines the correlation between the amplitudes and phases of the harmonic components of the gas pressure torque and the MIP of the engine. In the second part of the paper the statistical model is used to calculate the MIP and to detect deficient cylinders in the operation of a six-cylinder four-stroke diesel engine.

Issue Section:
Internal Combustion Engines
Keywords:
internal combustion engines, statistical analysis, pressure, torque, Fourier series, dynamic response, correlation methods
Topics:
Cylinders, Engines, Pressure, Torque
1.
Klauber, R. D., Vigmostad, E. B., Van Gerpen, D., Sprague, F. P., and Reiter, F. J., 1992, “Miniature Magnetostrictive Misfiring Sensor,” SAE Paper No. 920236.
2.
Garshelis, I. J., Aleksonis, J. A., Jones, C. A., and Rotay, R. M., 1997, “Development of a Magnetoelastic Torque Transducer for Automotive Transmission Applications,” SAE Paper No. 970605.
3.
Rizzoni, G., 1989, “Diagnosis of Individual Cylinder Misfires by Signature Analysis of Crankshaft Speed Fluctuations,” SAE Paper No. 89884.
4.
Brown, T. S., and Neil, W. S., 1992, “Determination of Engine Cylinder Pressures From Crankshaft Speed Fluctuations,” SAE Paper No. 920463.
5.
Citron S. J., O’Higgins, J. E., and Chen, L. Y., 1989, “Cylinder by Cylinder Engine Pressure and Pressure Torque Waveform Determination Utilizing Speed Fluctuation,” SAE Paper No. 890486.
6.
Rizzoni
,
G.
,
1989
, “
Estimate of Indicated Torque From Crankshaft Speed Fluctuations: A Model for the Dynamics of the I.C. Engine
,”
IEEE Trans. Veh. Technol.
,
38
(
3
), pp.
168
–
179
.
7.
Chen, K. S., and Chen, S., 1993, “Engine Diagnostics by Dynamic Shaft Measurement: A Progress Report,” SAE Paper No. 932412.
8.
Taraza, D., 1993, “Possibilities to Reconstruct Indicator Diagrams by Analysis of the Angular Motion of the Crankshaft,” SAE Paper No. 932414.
9.
Champoussin, J. C., and Ginoux, S. 1997, “Engine Torque Determination by Crank Angle Measurements: State of the Art, Future Prospects,” SAE Paper No. 970532.
10.
Guezenec, Y. G., and Gyan, Ph., 1999, “A Novel Approach to Real-Time Estimation of the Individual Cylinder Combustion Pressure for S.I. Engine Control,” SAE Paper No. 1999-01-0209.
11.
Gyan, Ph., Ginoux, St., Champoussin, J. C., and Guezennec, Y., 2000, “Crankangle Based Torque Estimation: Mechanistic/Stochastic,” SAE Paper No. 2000-01-0559.
12.
Williams, J., 1996, “An Overview of Misfiring Cylinder Engine Diagnostic Techniques Based on Crankshaft Angular Velocity Measurements,” SAE Paper No. 960039.
13.
Taraza, D., Henein, N. A., and Bryzik, W., 1996, “Experimental Determination of the Instantaneous Frictional Torque in Multi-cylinder Engines,” SAE Paper No. 962006.
14.
Maass, H., and Klier, H., 1981, Kraefte, Momente und deren Ausgleich in der Verbrennungskraftmaschine, Springer, Wien.
15.
Hafner, K. E., and Maass, H., 1985, Torsionsschwingungen in der Verbrennungskraftmaschine, Springer-Verlag, Wien.
16.
Taraza, D., 1997, “A General Theory of V-Engines Balance as a Predictive Tool in Engine Design,” Proceedings of the Fall Technical Conference, ASME, New York, ICE-Vol. 29-1, pp. 29–37.
17.
Ventsel, H., 1973, The´orie des Probabilite´s, E´ditions Mir Moscou, Moscow.
18.
Taraza
,
D.
,
2000
, “
A Probabilistic Approach to Engine Balance
,”
ASME J. Eng. Gas Turbines Power
,
122
, pp.
526
–
532
.
19.
Taraza, D., 2000, “Statistical Correlation Between the Crankshaft’s Speed Variation and the Contribution of Individual Cylinders to the Total Engine Output,” Proceedings of the Fall Technical Conference, ASME, New York, ICE-Vol. 35-3, pp. 81–93.
Copyright © 2003
 by ASME
You do not currently have access to this content.