Identification of complex flows in Taylor-Couette counter-rotating cavities

The transition in confined rotating flows is a topical problem with many in dustrial and fundamental applications. The purpose of this study is to inve stigate the Taylor-Couette flow in a finite-length cavity with counter-rota ting walls, for two aspect ratios L=5 or L=6. Two complex regimes of wavy v ortex and spirals are emphasized for the first time via direct numerical si mulation, by using a three-dimensional spectral method. The spatio-temporal behavior of the solutions is analyzed and compared to the few data actuall y available. (C) 2001 Academic des sciences/Editions scientifiques et medic ales Elsevier SAS.