The occurrence of shock wave in nozzle and the blockage of fluid at the so called "second throat" are closely related to the drainage structure of supersonic separator, which result from the thickening of the boundary layer owing to the interaction between boundary layer and shock waves. Two types of drainage structures are proposed to solve the above problems and promote the separation performance for gas purification. The CFD modeling is used to optimize and evaluate the different drainage structures. The results show that the cylindrical drainage and the cascade drainage can efficiently alleviate or remove the mass accumulation at the "second throat". The cascade drainage with reflux channel and oblique openings is superior to other drainage structures, due to the low flow velocity and high centrifugal acceleration in the drainage section. The flow velocity and temperature in the cascade drainage chamber with reflux channel are opposing for separation performance of the supersonic separator. It means that high flow rate in cascade drainage section will lead to lower temperature, but increase the number of droplets carried by airflow, and vice versa.

喷嘴中冲击波的发生和所谓的“第二喉道”处的流体阻塞与超音速分离器的排水结构密切相关，超音速分离器的排水结构是由于边界层与冲击波之间的相互作用而使边界层变厚所致。 。为了解决上述问题并提高气体净化的分离性能，提出了两种类型的排水结构。CFD建模用于优化和评估不同的排水结构。结果表明，圆柱形排水和梯级排水可以有效地减轻或消除“第二喉道”处的质量积聚。带有回流通道和倾斜开口的梯级排水优于其他排水结构，由于排水段流速低，离心加速度高。在具有回流通道的级联排水室中，流速和温度对超音速分离器的分离性能是相反的。这意味着级联排水段的高流速将导致较低的温度，但会增加气流携带的液滴数量，反之亦然。