Abstract:

A condition monitoring technique is developed for engines and similar machines whereby only external response measurements are used to determine the condition of the machine. The method assumes the response signal is composed of components due to an event of interest and other events which are not of interest. The response due to the events of no interest are treated as deterministic noise. An identification process is used to identify the noise and the frequency response function between the event of interest and the response. This identification procedure uses operating conditions which span the faults of interest. This model is used in an inverse filter process to determine the excitation during operation. Signal filtering and time gating are used to enhance the procedure. The method is verified for combustion faults on a diesel engine. [See NOISE-CON Proceedings for full paper.]