Experimental study of the wall surfaces 'roughness influence on the hydrodynamics' instabilities in a Couette-Taylor flow

Lamia Gaied , Emna Berrich (1, 2) , Maxence Bigerelle (3, 4) , Fethi Aloui (3, 4)

1 IMT Atlantique - DSEE - Département Systèmes Energétiques et Environnement
2 GEPEA-VERTE - Valorisation Energie-matière des Résidus et Traitement des Emissions
3 LAMIH - Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201
4 INSA Hauts-De-France - INSA Institut National des Sciences Appliquées Hauts-de-France

The Couette-Taylor flow starts with a laminar azimuthal state at low rotational speed, going to an intermediate regimeby increasing rotational speed with counter-toroidal cells (first instability or Taylor Vortex Flow). Beyond a critical value of rotational speed, various wavy modes break out first, then the flow becomes turbulent.The onset of instabilitiesdepends on the geometry of the system which we use.The aim of this study is to characterize the instabilities(Ta)then to study the effect of surface roughness on the hydrodynamic structures of Couette-Taylor Flow. So different surface conditions for inner cylinder were analyzed: smooth, sandpaper P180 and canvas plastic with different size-mesh.Characterizing the Couette-Taylor flow, a transition point (TVF to WVT) (WVF to MWVF) (MWVF to TTVF) was found to be influenced by surface roughness.For this, a qualitative study using reflecting kalliroscope particles was developed to visualize different flow regimes (Taylor vortex flow, wavy vortex flow, modulated wavy vortex flow and turbulent flow) in both smooth and rough walls. Then a quantitative study is investigated. Theresults showed that the surface roughness has an effect on the appearance of the instability of Taylor.

Mots clés: Taylor-Couette Flow; roughened surface; Visualization by kalliroscope particles

Domaines: Génie des procédés; Génie chimique

Lamia Gaied, Emna Berrich, Maxence Bigerelle, Fethi Aloui. Experimental study of the wall surfaces 'roughness influence on the hydrodynamics' instabilities in a Couette-Taylor flow. 23èmeCongrès Français de Mécanique, Aug 2018, Lille, France. ⟨hal-02407499⟩