@inproceedings{9e42a515944644af8d8df033d10cce97,
title = "Global optimal perturbations in a separated flow over a backward-rounded-step",
abstract = "We study through numerical instability analysis the linear three-dimensional dynamics of a recirculation bubble by separating the large-time dynamics from the short-time dynamics. In the former a global mode analysis is used to identify the three-dimensional bifurcation, analyse the structure of the leading global mode and identify the large-time optimal initial perturbation. In the latter an optimal perturbation analysis reveals that the shear layer of the recirculation bubble allows for intense amplification of the energy for two and three-dimensional initial perturbations. In both cases, the perturbations leading to the most amplification take the form of wave packet initially located in the vicinity of the separation and advected downstream along the separation line of the recirculation bubble. The short-time dynamics is characterized by an optimal time Topt leading to the maximum amplification of the energy for any initial optimal perturbations. Physically it corresponds to the time of transport of the perturbation by the base flow over the length of the recirculation bubble.",
author = "O. Marquet and D. Sipp and L. Jacquin",
year = "2006",
month = jan,
day = "1",
doi = "10.2514/6.2006-2879",
language = "English",
isbn = "1563478102",
series = "Collection of Technical Papers - 36th AIAA Fluid Dynamics Conference",
publisher = "American Institute of Aeronautics and Astronautics Inc.",
pages = "163--172",
booktitle = "Collection of Technical Papers - 36th AIAA Fluid Dynamics Conference",
note = "36th AIAA Fluid Dynamics Confernce ; Conference date: 05-06-2006 Through 08-06-2006",
}