Structure improvements and performance study of Supersonic Separation device with reflux channel

Abstract

A new supersonic separator with reflux channel has been proposed to obtain better refrigeration and separation performance. However, the specific structure of the new separator has not been reported so far. Moreover, the length of the conical drainage structure is too short to allow sufficient time to discharge the condensate. Therefore, in the paper, a new hybrid two-stage drainage structure is designed by adding additional side drainage structure after the conical drainage structure. Effect of the above structure changes on separation performance are investigated with three-dimensional numerical simulation. The results show that the increasing of reflux can greatly optimize the flow field. As the reflux flow increases, the shock wave position moves backwards and the condensation area is expanded. At the same time, the centrifugal acceleration decreases which can be overcome by optimizing the exit angle of swirler blades. The hybrid two-stage drainage structure extends the condensation area and prolongs the time of the condensate through the outlet. Moreover, the insertion depth of 30mm, the diameter of the reflux outlet of 7mm and the diameter of the reflux channel of 24 mm are recommended based on the comprehensive consideration of good expansion characteristics and the location of the shock wave.