2003-01-0354 Nonlinear Analysis of Combustion Engine Vibroacoustic Signals for Misfire Detection

To stop the rapid automobile-related deterioration of the environment, a number of rigorous regulations and requirements have been introduced (e.g. on-board diagnostic system OBDII/EOBD). One of the most important functions of the OBDII system is a misfire detection. The misfire detection capacity is essential not only because it helps to control exhausts emissions, but also because it aids in preventing damage to the catalytic converter. The years to come will see increasingly stringent norms in general, in particular the locomotive diesel engines area also. This paper presents results of research on nonlinear analysis of vibro-acoustic signals obtained from a combustion engine (locomotive diesel engine and automobile engines) which pertain to misfire detection. The results of the analysis demonstrate the dominant Lyapunov exponents in the case with all the cylinders are in operation to be differing considerably from the condition with one cylinder disconnected.