Research On The Visualization And Defoaming Method Of Bubble Flow In An Open Tank

Air mixed into oil reduces the performance and even affects the normal operation of the hydraulic system and the lubricating system.In this paper,numerical simulation and visualization experiment are used to investigate the oil inside the open tank.For investigating the formation process of bubbles,the movement regulation,a visualization experimental platform was set up,a visualization device was set up at key positions,A camera and a highspeed camera were used in the experiment to photo the two-phase flow of these key positions.According to the results which compared with the numerical calculation results,three methods for reducing bubbles were designed.The optimal structural parameters were determined according to the numerical calculation results.The bubble eliminating devices were tested on the visualization experimental rig.The experiment results show that the three bubbledischarging schemes can remove air bubbles and it’s valuable in the open oil tank.The major investigate contents of this paper are summarized as follows:Chapter 1 describes the various ways in which air enters oil and its presence in oil.It analyzes the effects of air bubbles in the normal system,and describes the study results of air bubbles both here and other country.Research status of bubble removal methods.Chapter 2 expounds the numerical simulation method for process of the air entrained the oil.Choose the Eulerian-Eulerian multiphase flow model and VOF model in software FLUENT for simulation calculation,and analyzes results of the simulation.In Chapter 3,a visualization experimental system with transparent pipes on the key positions was built.The movement regulation of bubbles in the oil was studied through the visualization experiment.Comparing the visualization experiment results with the simulation data of chapter 2,it is found that a large amount of air is entrained by the oil at the return port of the tank,and the oil moves continuously in the oil tank,the large air bubbles break into small bubbles during the oil moves continuously in the oil tank.Some of the bubbles float out of the oil,and some of them are sucked into the hydraulic system.at the same time,bubbles adhere to and remain in the transparent pipes.In Chapter 4 proposes three eliminating bubbles methods for the oil tank.The effects of structural parameters of three methods on eliminating air efficiency were studied by numerical simulation and theoretical analysis.The size of the cyclone,the position and shape of the baffles were determined to provide theoretical parameters for the processing experimental setup below.In Chapter 5,the experimental device for eliminating bubbles is completed,and the experiment of degassing device is carried out on the constructed visual test bench.The experimental results show that the three kinds of methods have obvious effect,and This paper provides a certain reference in how to reduce the oil in the oil tank.The summary and outlook summarizes the research results of this topic,and gives some suggestions for continuing the research of this topic.