Pseudo cylinder pressure excitation for analyzing the noise characteristics of the engine structure

Abstract A new in-cylinder excitation system has been developed to analyze the engine structure attenuation experimentally. A hydraulic and a piezoelectric actuator are used to exactly reproduce the cylinder pressure in non-running engine conditions. The structure attenuation measured in this system has a good coincidence with that measured in actual engine operating conditions, however the conventional excitation method, which applied only high-frequency components as the excitation pressure, resulted in poor agreement. As a result, the proposed system has been proved to be very useful and effective to estimate the engine noise characteristics without engine running.