Direct numerical simulation of a single bubble rising along an inclination wall

3D direct numerical simulation of single bubble rising along an inclination wall in high viscous fluid is conducted to investigate the bubble motion mechanism and the bubble-wall interaction in the vicinity of the wall based on the front tracking method. Bubble deformation, rising trajectory and velocity are calculated under different inclination angles (10°, 30° and 50°) under two different Eotvos number case (0.7 and 10) to check the inclination wall effect on the nearly undeformed bubble and the bubble with large deformation. The bubble is compressed a prolate spheroid and more asymmetric shape is obtained with larger tilt angle, which will bring on the asymmetric velocity field around the bubble, and it suggests that the suppression of the wall-normal velocity component is the source of the wall-induced lift force to balance the wall normal component of gravity experienced by the bubble. Consistent with experiment, the bubble rising velocity decreases monotonously with increasing the inclination angle. The good agreement of rising velocity between experimental and numerical results verifies the validity of our numerical method and the successful extension from single bubble rising near a vertical wall to rising along an inclination surface.