Optimal component mode synthesis for medium frequency problem

Mathieu Herran (1, 2) , Daniel Nélias (3, 2) , Alain Combescure (3, 4) , Hervé Chalons (1)

1 Turbomeca
2 MULTIMAP - Mécanique multiphysique pour les matériaux et les procédés
3 LaMCoS - Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne]
4 MIMESIS - Mécanique Multiéchelle pour les solides

The component mode synthesis (CMS) with fixed interface (denoted Craig–Bampton) method uses a combination of static and dynamic modes. The usual definition of this CMS leads to a coupling between static and dynamic modes which are not orthogonal with respect to the stiffness matrix. This type of basis is not well suited for dynamic explicit computations, because the resulting mass matrix is not diagonal. If one keeps the same basis mode set but uses an orthogonalization process with respect to the mass matrix, the quality of the reduced Craig–Bampton system is kept but the basis vectors are combined differently. The aim of this paper is to propose a new way to control the accuracy of the reduced dynamic system for a specific frequency domain. Thus a new CMS is defined in order to be accurate in the medium frequency range.

Mots clés: central difference integration; super-element impedance; component mode synthesis; dynamic substructuring; Craig–Bampton method; medium frequency range

Domaines: Sciences de l'ingénieur [physics]; Mécanique des solides [physics.class-ph]

Mathieu Herran, Daniel Nélias, Alain Combescure, Hervé Chalons. Optimal component mode synthesis for medium frequency problem. International Journal for Numerical Methods in Engineering, 2011, 86 (3), pp.301-315. ⟨10.1002/nme.3064⟩. ⟨hal-01372210⟩