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The paper presents an energetic post-processing methodology for large-scale vibro-acoustic finite element models. Starting from a dynamic and an acoustic modal basis produced by a finite element analysis (FEA), the methodology produces: 1 synthetic and pertinent energetic outputs; 2 optimal SEA partitions of the finite element mesh; 3 quality indicators of existing SEA partitions. The methodology involves six different steps, some required, some optional: 1 automatic partitioning of the FEA model in patches; 2 calculation of distribution matrices; 3 definition of mechanical loads; 4 definition of damping characteristics; 5 modal-based vibro-acoustic response calculation; 6 energetic post-processing; 7 automatic partitioning in SEA subsystems; 8 verification of existing SEA partitions. Each step will be presented in turn. The methodology will be illustrated by application of the successive steps to a Renault Laguna body and an Alstom two-storey TGV train section.

Due to the increasing focus on noise and vibration for future vehicles, there is a need for a clear definition of the requirements between vehicle manufacturers and auxiliary suppliers. Auxiliary characterisations are also needed as input for structure-borne numerical prediction models. Strongly coupled systems are amongst the most difficult structure-borne noise issues, as the transmitted forces and powers are strongly dependent upon the mobilities of both the vibration source and receiver. The so-called “blocked forces” can be used as intrinsic source descriptions. The challenge is then to design auxiliary test benches perfectly rigid in the frequency range of interest. The current paper is based on the French research program MACOVAM dedicated to the vibro-acoustic characterisation of oil pumps for truck engines. An original test bench was designed to measure quasi-blocked forces over the [150 Hz-2800 Hz] frequency range.