Topical Problems of Fluid Mechanics


logo UT logo CTU logo MIO Universite logo ERCOFTAC
Institute of Thermomechanics AS CR, v.v.i. CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics MIO Université du Sud Toulon Var - AMU - CNRS - IRD Czech Pilot centre ERCOFTAC
Occurrence of Taylor-Dean Instability in Flow Between Horizontal Coaxial Rotating Cones

Y. Hamnoune, F. Yahi, A. Bouabdallah

Abstract:
The present work is concerned with an experimental study of free surface effect on the onset of the Taylor-Dean instability. The experimental device consists of two horizontal coaxial truncated cones, the inner cone is rotating and the outer one is at rest. The cones have the same apex angle giving a constant radial gap. The rotational speed variation occurs in a quasi-static mode. This is to highlight the occurrence conditions of the Taylor-Dean instability in this kind of flow system by using two photometry techniques (transmission and reflexion of natural light). Therefore, by varying the aspect ratio Γ = H/d in the range 6.71 ≤ Γ ≤ 13.95 we examine the interaction of free surface on the appearance of Taylor-Dean instability in laminar-turbulent transition. In each case, one measures the features of the associated structures in vicinity of the critical points of their appearance. The obtained results are compared with the classical cylindrical Taylor-Dean flow system. The main result is to find that the occurrence of the instabilities is only limited to the primary mode in the conical flow system. The triplet mode is not observed in our case.

Keywords:
horizontal rotating coaxial cones, aspect ratio, free surface, laminar-turbulent transition regime, primary mode
Fulltext: PDF
DOI: https://doi.org/10.14311/TPFM.2017.020
In Proceedings Topical Problems of Fluid Mechanics 2017, Prague, 2017 Edited by David Šimurda and Tomáš Bodnár, pp. 153-158
ISBN 978-80-87012-61-1 (Print)
ISSN 2336-5781 (Print)
imce   Powered by Imce 3.0  © 2014, Pavel Formánek, Institute of Thermomechanics AS CR, v.v.i. [generated: 0.1222s]