IDENTIFICATION OF DIESEL FRONT SOUND SOURCE BASED ON CONTINUOUS WAVELET TRANSFORM

摘要

Acoustic signals from diesel engines not only contain useful information but also include considerable noise components.To extract information for condition monitoring purposes the continuous wavelet transform (CWT) is used for the characterization of engine acoustics.The characteristics of the CWT in terms of the representation of short duration transient signals are reviewed firstly.Wavelet selection and CWT implementation are then detailed.With the wavelet transform,the major sources of the exterior radiation sound of the engine front are surveyed.The research provides a reliable basis for engineering practice to reduce vehicle sound level.Furthermore,the identification results of the measured acoustic signals are compared with the identification results of the measured surface vibration,and good agreement is observed.