ADAPTIVE MODEL OF ENGINE VIBRATION SIGNAL FOR DIAGNOSTICS OF MECHANICAL DEFECTS

Abstract

An engine vibration and noise signal being applied for the engine combustion assessment contains also information on: a valve clearance, head gasket damage and wearing out of elements of a vehicle drive system. As the engine mileage increases the wearing out of driving system elements also increases, and in consequence the characteristics of vibration and noise generated by individual sub-assemblies are changing. Diagnosing of defects can be performed on the grounds of the model-based vibroacoustic signal by comparing the measured signal with this model. However, this model should be adapted after each changes of driving system elements and after each engine overhaul. Thus, it should be easily and fast automatically identifiable. Methods of generating the base model and its identification were proposed. The model based diagnostic method was verified – in the paper - on the example of the engine exhaust valve defect.

DOI: http://dx.doi.org/10.5755/j01.mech.19.3.4658