Internal combustion engine noise analysis time-frequency distribution

An analysis procedure, using the time frequency distribution, has been developed for the analysis of internal combustion engine noise signals. It provides an approach making use of advantages of both the linear time frequency distribution and the bilinear time-frequency distribution but avoiding their disadvantages. In order to identify requirements on the tune frequency analysis and also correlate a tune frequency analysis result with noise sources, the composition of the noise signal is discussed first. With this discussion, a mathematical model has been suggested for the noise signal. An example of identifying noise sources and detecting the abnormal condition of an injector with the noise signal tune frequency distribution for a diesel engine is also provided.