• Corpus ID: 239009700

Weak nonlinearity for strong nonnormality

  title={Weak nonlinearity for strong nonnormality},
  author={Yves-Marie Ducimeti{\`e}re and Edouard Boujo and F. Gallaire},
We propose a theoretical approach to derive amplitude equations governing the weakly nonlinear evolution of nonnormal dynamical systems, when they experience transient growth or respond to harmonic forcing. This approach reconciles the nonmodal nature of these growth mechanisms and the need for a center manifold to project the leading-order dynamics. Under the hypothesis of strong nonnormality, we take advantage of the fact that small operator perturbations suffice to make the inverse resolvent… 

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