| Ejector that is used in gas turbo-charged mining process is of low efficiency and inconvenient to adjust, while pressure exchange technology can achieve energy transfer between fluids directly by pressure waves and have high isentropic efficiency. So, pressure exchange technology is engineered into ejector, which is called gas wave ejector.In this paper, gas wave ejector was the main research object, whose performance was analyzed and investigated by using the method of numerical simulation and experimental study. The following work has been done in this dissertation:(1) The wave movement in gas wave ejector was analyzed in detail using one-dimensional theory of gas dynamics. The position of three ports could be fixed by calculating the velocity of shock wave and expansion fan.(2) A multi-period numerical model of gas wave ejector was set up to analyze the internal dynamics fluid flow, and then the wave pattern of gas wave ejector was drawn to predict the performance of gas wave ejector. Based on the simulation results, we could make a comparison of the performance of gas wave ejector and normal ejector. From the comparison, we may find that gas wave ejector has obvious advantages at a low pressure ratio.(3) The workflow chart of experiments was designed, and experimental system of gas wave ejector was established. Venturi flow meter was designed to measure the mass flow of the high-pressure nozzle, and experiment was presented to calibrate the venturi flow meter. Put forward experimental method, and studied medium pressure, angular speed, deflection distance, wall distance, nozzle size and clearance on the impact of equipment performance. The relations of isentropic efficiency and entrainment ratio varying with these parameters were revealed, then the inner mechanism was found to analyze by numerical model. The conclusion is that there are relational matches among these parameters, which can play a guiding role of enhancing the equipment performance.(4) Feedback structure was invented to recycle the medium-pressure gas in order to serves to modify the gas wave ejector performance characteristics in a manner which enables higher driving pressure ratios (PH/PM) to be used more effectively. Numerical simulation and experiment validation of feedback structure have been adopted. The experimental results show that feedback structure may improve the high-pressure-ratio equipment performance. When pressure ratio is 2, isentropic efficiency and entrainment ratio may increase by 6% and 0.05 respectively, so feedback structure has a good effect.
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