Analysing the dynamic behaviours of structures, whether in the framework of studying their linear vibrations or not, coupled multiphysics and vibroacoustics problems, problems of transient responses and high-speed dynamics, lead to building models that require huge numerical resources. Such models are often difficult to implement or reveal themselves to be poorly adapted when using such analyses in iterative optimisation procedures applied to exploring the preliminary design of a large number of configurations of the same system and for varied and/or extended ranges of frequencies. This is also the case when designing real-time diagnostics systems and implementing them in embedded mechatronic systems.

Using scale models is one of the methods that the VAST topic has developed and used for twenty years to deal with these problems. These models provide it with efficient and robust simulation tools perfectly adapted to the type of simulation considered and the numerical resources available. The techniques of reducing the models used classically in structural dynamics, based on the utilisation of modal bases and on experimental modal analysis, are extended to nonlinear problems and Multiphysics problems. Current efforts consist in completing these approaches by meshless type models. Continuous models of structural elements made of orthotropic materials are being developed in the framework of the Dynamic Stiffness Method and utilised for the design of smart structures.

Regular industrial partnerships lead to the exploitation of these approaches to develop operational tools that respond precisely to the demands of designers. (Renault, Thales, etc.).

Figure 1: Meshless type continuous model

The team’s activities are focused on transport technologies (aeronautics, aerospace, automobiles, railways, and marine transport), civil structures subject to dynamic stresses and energy production systems. These activities are carried out in partnership with industrial groups (AIRBUS, ARIANE Group, SAFRAN, RENAULT, PSA, PTC (FAYAT), JPB SYSTEME, KEYPROD, NEXTER, ALSTOM, etc.) and partner laboratories (ONERA, LAMCOS INSA Lyon, ROBERVAL – UTC, Institut NAVIER – ENPC, etc.).