Study on the Influence of the Throat Height of the Injector of the Self-circulating Treatment Casing on the Rotor Performance

Taking NASA Rotor 37 as the research object, the influence of the circulating mass flow rate of the self-circulating treatment casing(SCT) on the rotor performance was studied by numerical simulation method. The regulation of the circulating mass flow rate was realized by adjusting the injector throat height of the self-circulating treatment casing. It is found that the injector throat height has an important influence on the enhancing stability effect of the self-circulating treatment casing. As the injector throat height increases, there are three trends that the stall margin improvement of rotor increases slowly, then sharply increases, and finally increases to be flat. In addition, the efficiency of the rotor after the self-circulating treatment casing of the different injector throat heights has decreased. The reason for the decrease in efficiency is mainly due to the mixing loss and viscous dissipation loss of the blade tip exacerbated by the high-speed injecting from the injector, resulting in high loss area in the rotor tip region, which causes the rotor efficiency to decrease. And as the throat height of the injector increases, the greater the internal viscous dissipation of the flow, the greater the impact on the rotor efficiency.