https://hal-centralesupelec.archives-ouvertes.fr/hal-02307512Chitour, YacineYacineChitourL2S - Laboratoire des signaux et systèmes - UP11 - Université Paris-Sud - Paris 11 - CentraleSupélec - CNRS - Centre National de la Recherche ScientifiqueKateb, D.D.KatebLMAC - Laboratoire de Mathématiques Appliquées de Compiègne - UTC - Université de Technologie de CompiègneLong, RuixingRuixingLongGeneral Motors [Warren]Generic properties of the spectrum of the Stokes system with Dirichlet boundary condition in R-3HAL CCSD2016Navier-Stokes equationSimple eigenvaluesResonanceGenericity[SPI.AUTO] Engineering Sciences [physics]/AutomaticLE PIOLET, DELPHINE2020-04-03 09:44:552022-10-06 10:44:212020-04-07 14:30:23enJournal articleshttps://hal-centralesupelec.archives-ouvertes.fr/hal-02307512/document10.1016/j.anihpc.2014.09.007application/pdf1Let (S D-Omega) be the Stokes operator defined in a bounded domain Omega of R-3 with Dirichlet boundary conditions. We prove that, generically with respect to the domain Omega with C-5 boundary, the spectrum of (S D-Omega) satisfies a non-resonant property introduced by C. Foias and J.C. Saut in [17] to linearize the Navier-Stokes system in a bounded domain Omega of R-3 with Dirichlet boundary conditions. For that purpose, we first prove that, generically with respect to the domain Omega with C-5 boundary, all the eigenvalues of (SD Omega) are simple. That answers positively a question raised by J.H. Ortega and E. Zuazua in [27, Section 6]. The proofs of these results follow a standard strategy based on a contradiction argument requiring shape differentiation. One needs to shape differentiate at least twice the initial problem in the direction of carefully chosen domain variations. The main step of the contradiction argument amounts to study the evaluation of Dirichlet-to-Neumann operators associated to these domain variations. (C) 2014 Elsevier Masson SAS. All rights reserved.