Impacts Of Structural And Operating Parameters On The Ejecting Performance Of Pressure Oscillator Tube

Static ejector device is used in the traditional ejection process.In this paper,a two-open oscillator tube ejector is used as the research object.By means of one-dimensional theoretical calculation,two-dimensional numerical simulation and experimental study,the performance of the two-open oscillator tube ejector device is analyzed and studied.And the model and numerical analysis of a radial-flow two-open oscillator tube is presented.The main works and results are as follows:(1)The ideal wave diagram of wave rotor ejector is set up.The characteristics of various pressure waves are analyzed,and a one-dimensional theoretical analysis of the internal flow of the wave rotor is carried out by using the characteristics of the pressure waves and the basic principle of one-dimensional unsteady flow.In this paper,a one-dimensional calculation program is obtained,and the fluctuation characteristics of the two-open oscillator tube and the law of gas ejection in the device are revealed.(2)To study the motion of waves and contact surfaces within a wave rotor,a two-dimensional numerical model is established,and the flow characteristics of two-open oscillator tubes are revealed.In this paper,the characteristics of the steady region are analyzed and the influence law of the pressure in the steady region in the equipment performance is obtained.A numerical simulation of a four-port wave rotor is carried out to find out the cause of the poor ejection effect.(3)An experimental platform was established to conduct experimental study on the two-open oscillator tube ejector device.Through the experiment of vacuum degree,it is found that there is a direct ratio relationship between the vacuum degree and the entrainment ratio.By changing the expansion ratio and the MP port pressure,the effect of the two on the efficiency is obtained,and the reasons for the limitation of the use on the large expansion ratio are analyzed.By changing the frequency and the deflection,if the incident shock wave happens to get open-reflection when it gets to the right end of the oscillator tube,the efficiency is the best,and the smaller the deflection distance,the lower the optimal frequency.(4)Through the analysis of the experimental results of the inclined channel wave rotor,A numerical model of a radial-flow two-open oscillator tube is established for the numerical analysis,and the effect of MP port pressure on efficiency is analyzed.From the simulation results,it can be seen that the radial-flow structure,because of the use of motor power,adds a supercharging process,which greatly increases the entrainment ratio and efficiency,and the ejection rate can exceed 100%.