Experimental Study on the Effects of Surface Roughness on the Behaviors of Hydrodynamic Instabilities of Couette-Taylor Flow

Mostafa Monfared , Lamia Gaied , Emna Berrich (1, 2) , Ebrahim Shirani , Maxence Bigerelle (3) , Fethi Aloui (3)

1 GEPEA-VERTE - Valorisation Energie-matière des Résidus et Traitement des Emissions
2 UN - Université de Nantes
3 LAMIH - Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201

Couette-Taylor flow is a type of fluid flow that occurs in the annulus between differentially concentric cylinders, when the outer cylinder is fixed and the inner cylinder rotates and the rotation rate exceeds a critical value. In this research we have studied the effect of surface roughness on the hydrodynamic structures of Couette-Taylor Flow. The PIV technique has been applied for flow visualization. At first, for a smooth surface, the different flow patterns include Couette flow, Taylor vortex flow, wavy vortex flow, modulated wavy vortex flow and turbulent flow. They are investigated numerically and experimentally. The transition Taylor number for every flow regime is also taken into consideration. The results showed that the numerical results correspond quite well to the experimental data. Then, the different surface conditions for inner cylinder which are studied are: a smooth one, a sandpaper-type P180, a canvas plastic with different wire-mesh roughness. They are used to study the effects of surface roughness on the flow structures and critical Taylor numbers. The experimental results showed that the roughness causes a delay in the appearance of the first instabilities.

Mots clés: Couette-Taylor flow; Critical Taylor number; Hydrodynamic instability; PIV; Surface roughness; Couette-Taylor Flow Surface Roughness PIV Critical Taylor number Hydrodynamic instability; Couette-Taylor Flow; Surface Roughness

Domaines: Génie des procédés; Génie chimique

Mostafa Monfared, Lamia Gaied, Emna Berrich, Ebrahim Shirani, Maxence Bigerelle, et al.. Experimental Study on the Effects of Surface Roughness on the Behaviors of Hydrodynamic Instabilities of Couette-Taylor Flow. ASME 2017 Fluids Engineering Division Summer Meeting, Jul 2017, Waikoloa, United States. ⟨10.1115/FEDSM2017-69252⟩. ⟨hal-02407401⟩