Excitation analysis on resilient mounting eigenmodes of large-bore internal combustion engines

Start Page
4157
End Page
4171
Citation
30th International Conference on Noise and Vibration Engineering (ISMA 2022)
Contribution to Conference
30th International Conference on Noise and Vibration Engineering, ISMA 2022
Scopus ID
2-s2.0-85195919527
ISBN
[9789082893151]
Modern large-bore internal combustion (IC) engines are decoupled from the foundation using resilient rubber mounts. A resiliently mounted engine significantly reduces structure-borne noise (SBN) transmission from the engine as vibration source to the surrounding, e.g. a passenger or cruise ship. During Modal Analysis of such a system, particular Resilient Mounting Eigenmodes due to the rubber elements can be observed which have far lower eigenfrequencies than the engine's structural components. Therefore, it is a common assumption to consider the engine as rigid body in the design of the resilient mounting. This work discusses this simplification by carrying out a Harmonic Response Analysis for a rigid and an elastic engine model. It is shown how elasticity of the engine structure significantly changes the vibration response. Further, it is illustrated that the excitation of Resilient Mounting Eigenmodes is an intrinsic engine property and not coming from e.g. unbalances during the production process or other external sources as commonly assumed.