Noise Source Identification Under Steady and Accelerating Conditions on a Turbocharged Diesel Engine

THE MAIN AIMS of the experiments reported in this paper are to obtain a quantitative comparison between the noise ranking of engine components using intensity and lead wrapping techniques, and to analyze the causes of the sudden increase in noise level observed during the initial part of the acceleration process.

The results indicate that the surface intensity technique agrees well with the lead wrapping sound power results and, although the surface intensity technique in its present state of development, is still time consuming, it does also produce information about the vibration levels of the surface which is essential when the component has to be redesigned to reduce noise.

The acceleration test results indicate that the increased, sound pressure level is directly related to changes in the combustion process while turbocharger lag appears to have negligible effect.