Abstract
Because of difficulties of applying Transient Analysis in complex structure we use a set up of instruments by exploiting the experimental results of known structures of engines.
Considering the combustion process as a dynamic excitation, we measure the noise and teh vibration on chosen points on a Spark Ingnition (S.I) engine and a Compression Ingnition engine (C.I). By doing that we come no conclusions concerning the combustion flow.
In this experimetnal work appear the spectra of the noise and vibration measurements in connection with the R.P.M. fo the engine. From the comparison between the spectra, we extract important results concerning the chanage of the combustion flow in every different type of engine in several stages.
The mesurements have been taken on a S.I. and C.I. engine in Special Engineering Laboratory.
