The Supersonic Two-phase Flow And The Design Of Ejector With Pressure Gain

Ejector with pressure gain has been used in a variety of applications due to their simplicity, reliability and versatility. Though the structure of ejector with pressure gain is very simple, the supersonic flow in the equipment is very complex because of the interaction of shock wave, boundary layer, and shear layer. The mix mechanism is not very clear. In this paper, begin with the calculation of the sound velocity and the analysis of the emergence of shock wave, we prepared an experiment for the further study of the characteristics of the ejector, supply the frame of reference for the design of geometrical factors and work factors. Main contributions of the paper are as follows:①Based on the law of two-phase flow in the ejector with pressure gain, according to its characteristic equation, full dimensions were designed, and the dimension of each part was given in detail.②According to the experiment, the pressure of exit hot water was more or less higher than the entrance working steam the maximum is up to 1.5 times. The effect of pressure gain was well proved. This was in good agreement with the theoretical analysis.③Increasing the pressure of working fluid is helpful for the eject coefficient and lift-pressure capability.④The higher the pressure of inject fluid, the easier it was sucked and the bigger the eject coefficient was.⑤The exit area of the nozzle and the throat structure of mixing chamber have great impact on eject coefficient.