Abstract
Hydraulic systems feature compact, high-output power and rapid response. However, when air bubbles are mixed into the hydraulic oil, they lower the efficiency of hydraulic systems and contribute to instrument malfunctions. Therefore, it is important to eliminate these bubbles from the oil. Our project team has been developing an active bubble elimination device termed a bubble eliminator, which removes air bubbles using a swirl flow. The shape of the device affects the removal performance, so the choice of shape parameters is key to improved performance of the device. The purpose of this study is to optimize the shape parameters of the bubble eliminator. We focus particularly on the optimal diameter of the vent port. In order to determine this parameter, flow behaviors in the bubble eliminator are investigated in the laboratory with transparent bubble eliminators and numerical analysis of the experimental conditions. The validity of numerical simulation is verified by comparing its results with flow patterns obtained from image photos of an experimental flow visualization. Numerical analysis is carried out under fixed conditions, and an optimal diameter for the vent port is determined.
