ENGINE NOISE CHARACTERIZATION WITH WIGNER-VILLE TIME-FREQUENCY ANALYSIS

Reduction in the sound emitted by engines requires accurate identification of the excitation and propagation mechanisms inside the engine. Time-frequency analysis of vibration signals picked up on the outside and inside of an engine cylinder enables us to link every event observed in the time-frequency plane to one excitation source. It is then possible to measure the energy of each event and to quantify the part of each excitation mechanism in the vibration energy which is emitted towards the outside of the engine. © 1993 by Academic Press, Limited.