Abstract
Air bubbles in hydraulic oil lower the efficiency of hydraulic systems and contribute to instrument malfunctions. To mitigate these problems, it is possible to use an active "bubble eliminator" that uses swirl flow to remove air bubbles. The device shape affects the efficiency of bubble removal; hence, the selection of geometry is the most important parameter for optimizing the device performance. This study investigates the effect of the shape parameters of the device on bubble behavior in the oil, using experimental flow visualization and numerical simulations of the device. In this paper, we conducted the experimental flow visualization and numerical simulation involving various diameters of an outlet port and vent port. The simulation results are analyzed using considering the relationship between axial flow and swirl flow in the bubble eliminator. We conclude that the diameters of the outlet port and vent port, and the length of the tapered tube of the bubble eliminator can be determined.
