Topical Problems of Fluid Mechanics


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

Influence of the Tilted Flow System on the Flow Between Rotating Conical Cylinders
F. Yahi, Y. Hamnoune, A. Bouabdallah
Abstract:
The present study is concerned with the tilted flow system effect on the flow between two coaxial cones. Our primary interests are to carry out a systematic experimental study, focusing on analysis of laminar-turbulent regime to highlight the appearance of different instability modes. The inner cone is rotating and the outer one is at rest. Both cones have the same apex angle Φ resulting in a constant width of the gap so that δ = d/R1max = 0.12 case of small gap configuration. The working fluid is Newtonian and has constant properties as density and viscosity within the range of the required experimental conditions. The observed phenomena were described for different aspect ratio Γ = H/d in the range of 15.5 ≤ Γ ≤ 32 and on the angular range 0° ≤ α ≤ 90° from the vertical axis (α = 0). These observations are carried out using two kind of visualization techniques (transmission and reflexion of the naturel light). The various obtained results are analyzed and compared systematically to the properties established in the case of vertical flow system.
Keywords:
conical cylinders, inclination effect, instability, laminar-turbulent transition regime, spiral mode

Fulltext: PDF DOI: https://doi.org/10.14311/TPFM.2018.044

In Proceedings Topical Problems of Fluid Mechanics 2018, Prague, 2018 Edited by David Šimurda and Tomáš Bodnár, pp. 333-340 ISBN 978-80-87012-65-9 (Print) ISSN 2336-5781 (Print)