Response Computation of Structures with Viscoelastic Damping Materials using a Modal Approach - Description of the Method and Application on a Car Door Model Treated with High Damping Foam

摘要

Numerous passive damping technologies including viscoelastic materials are used today in the design of automotive car bodies. Viscoelastic materials are characterized by properties that are frequency and temperature dependent. In many FE codes, their use in automotive models is limited in terms of capabilities and often results in excessive computation time. In the case of MSC/NASTRAN, for instance, there is neither possibility to define more than one viscoelastic material nor to introduce independent variations for tensile and shear moduli. Moreover, the efficient modal approaches must be put aside in favor of a direct resolution whose results, albeit accurate, cannot justify the increased computation time, especially for models with several million degrees of freedom. This paper presents a method, based on a modal approach and implemented in MSC/NASTRAN using the DMAP language, to overcome these limitations. It is followed by its application to a Peugeot 207 car door treated with a high damping foam.