42015-03-31 , 法政大学大学院デザイン工学研究科
Air bubble entrained in oils cause many problems, such as the acceleration of oil degradation, cavitation erosion, and decline of effective bulk modulus of oil. Air bubbles in working fluids must be actively separated and eliminated to realize performance improvement of hydraulic systems. To remove air bubbles from hydraulic oil, it is possible to use an active "bubble eliminator" that uses swirl flow to remove air bubbles. In this paper, the improvement of oil aging, cavitation erosion, and the effective bulk modulus by the bubble eliminator was experimentally investigated. Moreover, to enhance the performance of the bubble eliminator, experimental flow visualization and numerical simulation of the bubble eliminator were conducted, and the importance of design index of the bubble eliminator considering the fluid condition \WS mentioned. To establish the new design index of the bubble eliminator, the effect of the shape parameters of the device andfluid condition on the performance of the bubble eliminator was clarified. As a result, it became possible to design the bubble eliminator considering the fluid condition.