Diesel Engine Assembly Noise Assessment Using Dynamic Excitation

A method is presented to evaluate diesel engine structure borne noise differences caused by component design changes of the engine assembly. A flexible multi-body dynamics model is used to develop loads on the engine due to combustion, piston-liner interactions, and interactions at the main bearings. These loads are applied to an engine finite element model for frequency response analysis. The frequency response analysis is then varied by changing the component design of the engine assembly. Surface velocities and modal participation factors are determined from the frequency response. The participation factors are then used in a modal acoustic transfer analysis to compute the sound power. Comparisons are made between assemblies and to experimental data.