Bubble dynamics in a horizontal channel

Abstract

In the present study, bubble dynamics in a horizontal channel flow is investigated by conducting direct numerical simulations. The refined level set grid method is adopted for the interface tracking and the global mass correction method is used for a volume conservation. There are two different cases of bubble behaviors. To describe these phenomena, effects of bubble deformability and initial position are analyzed in various conditions. It is verified that the bubble behavior is determined by the shear lift force and the buoyancy force. The critical position of a deformable bubble is nearer to the wall than that of a less deformable case. In the less deformable case, a bubble moves like a rigid sphere, and it is possible to use a modeled equation for the rigid sphere to predict the bubble behavior. In the fully developed turbulent flow field, the critical position exists at the location which has a lower shear rate than that of the parabolic velocity profile condition.