Laminar-turbulent transition regimes in the conical Taylor-Couette flow system

¹ Thermodynamics and Energetic Systems Laboratory, Faculty of Physics, University of Sciences and Technology Houari Boumediene, B.P. 32 El Alia 16111 Bab Ezzouar, Algiers, Algeria.
² Genie Physical of Hydrocarbons Laboratory, Faculty of hydrocarbons and chemistry, University M’Hamed Bougara, 35000 Boumerdes, Algeria.
³ Laboratoire de Mécanique des Fluides et d’Acoustique, CNRS/ Université de Lyon, Ecole Centrale de Lyon/Université Lyon 1/INSA de Lyon, ECL, 36 Avenue Guy de Collongue, 69134 Ecully Cedex, France.
⁴ CETHIL, UMR CNRS 5008, Université de Lyon, INSA de Lyon/Université Lyon 1, INSA, Bâtiment Sadi Carnot, 9 rue de la Physique, 69621 Villeurbanne Cedex, France.
⁵ Department of Mechanical Engineering, Akita University, Tegata-Gakuen 1-1, Akita 010-8502, Japan.

^* Corresponding author: yahi.fatma@gmail.com

Published online: 12 May 2017

Abstract

The present work is intended to experimentally study the Taylor-Couette flow between coaxial cones. The inner cone is rotated and the outer cone is maintained fixed. Both cones have the same apex angle Φ =12°, giving a constant annular gap δ =0.12. The height of the fluid column is H=155 mm. The working fluid is assumed as Newtonian and has constant properties (as density and viscosity) within the range of the required experimental conditions. By means of visualization techniques, the critical thresholds related to the onset of various instabilities have been obtained and the corresponding flow modes have been identified. Using images processing, spatio-temporal diagrams have also been calculated, showing the characteristics (wavelength, drift velocity) of the downward helical motion. The results obtained for these transition regimes are compared to those of Wimmer et al. [1-3].