Interaction and drag coefficient of three horizontal bubbles with different sizes rising in the shear-thinning fluids - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue International Journal of Multiphase Flow Année : 2020

Interaction and drag coefficient of three horizontal bubbles with different sizes rising in the shear-thinning fluids

Résumé

The interaction and drag coefficient of three horizontal bubbles with a large bubble (BL) and two side symmetrical small bubbles (BS) in the shear-thinning fluids were simulated numerically using the three-dimensional volume of fluid (3D-VOF) method. The effects of the initial diameter of BL, initial bubble interval and liquid property on the rising velocity and drag coefficient of bubbles were studied. When the BL diameter increased, both the drag coefficients of BL and BS decreased. However, the initial bubble interval increased, the interaction between BL and BS became weakened, which caused the decrease of the drag coefficient of BL but the increase of the drag coefficient of BS. Moreover, the flow index n of liquid had also remarkable influence on bubble drag coefficient, as n decreased, the viscosity of the liquid would reduce, which facilitated the motions of BL and BS, thereby the drag coefficients of both BL and BS decreased. Furthermore, the ratios (φBL and φBS) of drag coefficients of BL and BS to corresponding freely rising single bubble were investigated quantitatively to characterize the interaction between bubbles. The φBL and φBS approached gradually to 1 with the increase of initial bubble interval, indicating that interaction between bubbles became weakened gradually. When the size of BL was increased, the influence of BS on BL would become decreased even negligible, however, the wake effect of BL on BS would be markedly enhanced, thus φBL decreased gradually to approaching 1, and meanwhile φBS would decline from near 1 and then be gradually far away. Besides, the φBL (> 1) decreased to approaching 1 gradually with the increase of flow index n, while the φBS (< 1) increased until close to 1. Moreover, two modified correlations of the bubble drag coefficient for the unequal multi-bubble system in the shear-thinning fluids were proposed, which showed considerable good prediction accuracy
Fichier non déposé

Dates et versions

hal-02447367 , version 1 (21-01-2020)

Identifiants

Citer

Wanpeng Sun, Chunying Zhu, Taotao Fu, Youguang Ma, Huai-Zhi Li. Interaction and drag coefficient of three horizontal bubbles with different sizes rising in the shear-thinning fluids. International Journal of Multiphase Flow, 2020, 125, pp.103214. ⟨10.1016/j.ijmultiphaseflow.2020.103214⟩. ⟨hal-02447367⟩
32 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More